Remedi screening just notes

Development of a broad toxicological screening technique for urine using ultra-performance liquid chromatography and time-of-flight mass spectrometry.

Lee HK, Ho CS, Iu YP, Lai PS, Shek CC, Lo YC, Klinke HB, Wood M.

Source

Department of Clinical Pathology, Tuen Mun Hospital, Tuen Mun, Hong Kong.

Abstract

Withdrawal of the support for the REMEDi HS drug profiling system has necessitated its replacement within our laboratories with an alternative broad toxicological screening technique. To this end, a novel method, based on ultra-performance liquid chromatography (UPLC) and time-of-flight (TOF) mass spectrometry, was developed for the routine analysis of urine samples. Identification was achieved by comparison of acquired data to libraries containing more than 300 common drugs and metabolites, and was based on a combination of retention time, exact mass and fragmentation patterns. Validation data for the method is presented and comprised an evaluation of the following parameters: precision; transferability of the methodology between the six collaborating laboratories; specificity; extraction recovery and stability of processed samples; matrix effects and sensitivity. This paper presents the benefits of supplementary fragmentation data with particular regard to increasing specificity and confidence of identification and its usefulness with overdosed samples. The utility of the method was assessed by the parallel analysis of 30 authentic urine samples using the REMEDi HS and UPLC-TOF. The latter provided enhanced detection, leading to the identification of twice as many drugs. Furthermore it did not miss any compounds that were identified by REMEDi HS. The UPLC-TOF findings were further verified by a combination of data from three other conventional screening techniques, i.e., GC-MS, HPLC-DAD and UPLC-MS/MS.

J Anal Toxicol. 2007 Jul-Aug;31(6):321-7.

Toxicological screening in urine: comparison of two automated HPLC screening systems, toxicological identification system (TOX.I.S.*) versus REMEDI-HS.

Schönberg L, Grobosch T, Lampe D, Kloft C.

Source

Berliner Betrieb fuer Zentrale Gesundheitliche Aufgaben (BBGes), Institute of Clinical Toxicology-Clinical Toxicology and Poison Control Centre, Oranienburgerstr. 285, D-13437 Berlin, Germany.

Abstract

In this paper, the comparison of two automated high-performance liquid chromatography (HPLC) screening systems, a newly developed toxicological identification system (TOX.I.S.) versus the commercially available Remedi-HS (Bio-Rad), is presented. Urine samples from 405 cases screened positive for amphetamines, cocaine, and opiates by immunological assays and confirmed by GC-MS were analyzed with both systems. In more than 80% (TOX.I.S.) and 78% (Remedi-HS) of the cases (except for cocaine), the results obtained by both HPLC methods showed agreement with the earlier obtained results by immunoassay prescreening and gas chromatography-mass spectrometry (GC-MS). The evaluation showed that both automated HPLC methods led to comparable results and can be used alternatively. As the confirmation results for cocaine were rather poor (45% TOX.I.S., 54% Remedi-HS) in comparison to GC-MS, the TOX.I.S. was further optimized for the detection of the cocaine metabolite benzoylecgonine (BEC). The BEC method improved the detectability of BEC from 45% to 80%. Besides confirmation screening, the use of both systems in cases of acute intoxications was investigated. Information about basic compounds was obtained from urine screening by both systems, which therefore were useful as complementary techniques in the toxicological laboratory. The TOX.I.S. offers advantages such as common equipment, modern software, and higher versatility with the opportunity to establish additional methods in the system.

J Anal Toxicol. 2006 Jan-Feb;30(1):61-4.

Performance characteristics of DRI, CEDIA, and REMEDi systems for preliminary tests of amphetamines and opiates in human urine.

Huang MK, Dai YS, Lee CH, Liu C, Tsay WI, Li JH.

Source

National Bureau of Controlled Drugs, Department of Health-Taiwan, 6 Linsen South Road, Taipei 10050, Taiwan, ROC.

Abstract

Arrestee urine specimens (930) were tested with DRI, CEDIA, and REMEDi; those that tested positive for amphetamines and opiates (616 and 414, respectively) were then confirmed by gas chromatography-mass spectrometry. The performance characteristics of these three preliminary systems were evaluated using the following commonly used parameters: true positive, true negative, false positive, and false negative. The sensitivity, specificity, and efficiency of these methods were also calculated. Data derived from this study indicated DRI and CEDIA adapted by this study generated acceptable preliminary test results for amphetamine/methamphetamine and morphine/codeine, but not for MDA/MDMA and REMEDi has lower sensitivity than DRI and CEDIA, but with better specificity and efficiency, supporting its use under emergency room settings where drug concentrations in overdose cases are expectedly at high levels.

Clin Chem Lab Med. 2004;42(9):1063-5.

Diagnostic efficiency of different amphetamine screening tests–the search for an optimal cutoff.

Savoca R, Rentsch KM, Hubert AR.

Source

Center of Laboratory Medicine, Kantonsspital Aarau, Aarau, Switzerland. reto.savoca@ksa.ch

Abstract

Increased use of designer drugs (amphetamines and amphetamine-like substances) raises the need for fast screening tests in urine in clinical settings, workplace and drug rehabilitation. Immunological assays currently used are subject to unwanted crossreactivities, partly depending on the cutoff concentrations used. The values recommended in Europe and the USA are 500 and 1000 ng/ml, respectively. In Switzerland, the recommended concentration of 300 ng/ml results in a high rate of false-positive urine samples and expensive, time-consuming confirmation testing. Using the Abbott Axsym analyzer, we found numerous false positives from patients in rehabilitation centers due to concomitant medication. Therefore, the diagnostic sensitivity and specificity of the Abbott test at different cutoff concentrations and the sensitivity of the Roche Cobas Integra, Beckman Synchron and Biosite Triage point-of-care test were examined. HPLC BioRad Remedi was chosen as the method of higher hierarchical order. The specificity of the Axsym analyzer (300 ng/ml) was 86%. At 500 ng/ml or 1000 ng/ml the specificity was increased to 99 or 100%, respectively, while the sensitivity only decreased from 97 to 91 or 81%, respectively. In summary, the cutoff concentration for amphetamine screening tests should not be below 500 ng/ml to avoid a high rate of false-positive results.

Am J Addict. 2004 Jul-Sep;13(4):398-404.

Prevalence of substance abuse among patients with physical diseases seen in an emergency room in Japan.

Hirabayashi N, Wada K, Kimura T, Hirabayashi E, Mishima S, Yukioka T, Hanaoka T, Iimori M.

Source

National Center Hospital for Mental, Nervous, and Muscular Disorders, Tokyo 187-8551, Japan. hirabaya@ncnpmusashi.gr.jp

Abstract

According to a nationwide general population survey on drug use in Japan, the lifetime prevalence of methamphetamine is low when compared to the United States. To confirm the hypothesis of a lower point prevalence of methamphetamine in an emergency room (ER) in Japan than in the United States, we collected blood specimens from an urban area of heavy methamphetamine prevalence in Tokyo, Japan, and analyzed the sera using REMEDi-HS based on an unlinked anonymity. Twenty kinds of drugs other than psychotropics were detected in 55 of 279 subjects (19.7%). Nineteen kinds of psychotropics were detected in twenty (7.2%) subjects. Psychotropics were detected in eleven patients with physical diseases and no acute intoxication. Methamphetamines were detected in three subjects (1.09%, 95% confidence interval 1.073-1.088) and in one of 46 subjects with injury (2.2%). It is necessary to look at the methodological differences between this study and previous studies; however, this finding supports the lower point prevalence of methamphetamine in an ER in Japan than in an ER in the United States.

Nihon Arukoru Yakubutsu Igakkai Zasshi. 2004 Feb;39(1):46-50.

[Prevalence of substance abuse through biological method among patients with physical diseases seen in an emergency room].

[Article in Japanese]

Hirabayashi N, Yukioka T.

Source

National Center Hospital for Mental, Nervous and Muscular Disorders, National Center of Neurology and Psychiatry, 4-1-1 Ogawahigashi-cho, Kodaira-city, Tokyo 187-8551, Japan.

Abstract

According to a nationwide general population survey on drug use in Japan, using self-administered questionnaires, the lifetime prevalence of methamphetamine usage was low, compared with those of Western countries. Recent validation studies suggested that only about half or less of the recent illicit drug abuse was self-reported and the biological measurement of drug abuse was necessary to evaluate the prevalence of the illicit drug abuse. We collected blood or urine specimens in an emergency room located in an urban area of Tokyo, Japan, and analyzed the sera or the urine, using REMEDi-HS based on an unlinked anonymous method from 2000 to 2002. The prevalence of the methamphetamine abusers aged form 10 to 60 yrs was 2.94, 7.02, and 5.63 each year. The mean prevalence of these three years was 5.20 (95% confidence interval 2.42-7.05). It is necessary to look at the methodological differences between this study and previous studies. This finding supports the lower point prevalence of methamphetamine usage in an ER of Japan rather than in an ER of the US. However, it is not necessarily lower than that of trauma patients in the urban area of the UK, or drivers, and the ER population in France.

 

Clin Chem. 2002 Oct;48(10):1715-9.

Excretion and detection of cathinone, cathine, and phenylpropanolamine in urine after kath chewing.

Toennes SW, Kauert GF.

Source

Institute of Forensic Toxicology, Center of Legal Medicine, University of Frankfurt/Main, Kennedyallee 104, D-60596 Frankfurt/Main, Germany. toennes@em.uni-frankfurt.de

Abstract

INTRODUCTION:

The stimulating herbal drug kath is uncommon in most countries, and information on its detection and interpretation of analytical results is limited. Therefore, a study with kath was carried out to compare the efficiencies of different analytical techniques used to detect drug use.

METHODS:

Four volunteers chewed kath leaves for 1 h; urine samples were collected up to 80 h afterward and analyzed by the Abbott fluorescence polarization immunoassay (FPIA), the Mahsan-AMP(300) on-site immunoassay, the Bio-Rad Remedi HS HPLC system with photodiode array detection (DAD), and gas chromatography-mass spectrometry (GC-MS).

RESULTS:

FPIA gave negative results, whereas positive results were obtained with the Mahsan test during the first day. With HPLC, one peak could be observed up to 50 h, but its DAD spectrum could not be identified by the system. Further investigations indicated that the kath alkaloids coeluted and produced a mixed DAD spectrum. With GC-MS, the specific kath ingredient cathinone was detected up to 26 h, whereas cathine and norephedrine were still detectable in the last samples. Maximum concentrations of cathinone, cathine, and norephedrine in urine samples from the study were 2.5, 20, and 30 mg/L, respectively, whereas in authentic cases the concentrations were much higher.

CONCLUSION:

GC-MS is superior to the screening techniques Mahsan-AMP(300) and Remedi with respect to specificity and sensitivity for the detection of kath use in urine.

Zhonghua Nei Ke Za Zhi. 2002 Jun;41(6):408-10.

[The application of a broard spectrum automatic rapid drug identification system in acute drug poisoning].

[Article in Chinese]

Wang H, Niu W, Zhang J, Sun C.

Source

The Second Department of Internal Medicine, The Affiliated Hospital of Academy of Military Medical Sciences, Beijing 100039,China. hanbin-w@yahoo.com

Abstract

OBJECTIVE:

To describe the usefulness of REMEDi HS in the diagnosis of acute drug poisoning patients.

METHODS:

Samples from 1 200 drug poisoning patients were analysed with REMEDi HS. REMEDi HS is a broad spectrum rapid drug identification system, designed for emergency toxicology screening and forensic applications. The total analysis time is about 30 min. The current library of the system has 916 drugs and their metabolites.

RESULTS:

Among the 1 200 poisoning patients identified by REMIDi HS, the most frequently encountered drugs were benzodiazepines, phenothiazine anti-psychotics, non-phenothiazine anti-psychotics, tricyclic anti-depressants and opioid analgesics. Estazolam (10.25%)diazepam (9.25%)cimetidine (4.33%)chlorpromazine (3.50%)clozapine(2.75%)caffeine (2.58%)nikethamide (2.42%)morpine (1.92%)lidocaine (1.75%) and alprazolam (1.50%) are the ten drugs of highest frequency identified.

CONCLUSIONS:

Our study demonstrated that REMEDi HS is particularly useful for rapid measurement of drug concentration in the samples from acute poisoning patients.

J Anal Toxicol. 2002 Apr;26(3):181-6.

Immunoassay screening of lysergic acid diethylamide (LSD) and its confirmation by HPLC and fluorescence detection following LSD ImmunElute extraction.

Grobosch T, Lemm-Ahlers U.

Source

Berliner Betrieb für Zentrale Gesundheitliche Aufgaben (BBGes), Klinische Toxikologie und Pharmakologie, Berlin, Germany.

Abstract

In all, 3872 urine specimens were screened for lysergic acid diethylamide (LSD) using the CEDIA DAU LSD assay. Forty-eight samples, mainly from psychiatric patients or drug abusers, were found to be LSD positive, but only 13 (27%) of these could be confirmed by high-performance liquid chromatography with fluorescence detection (HPLC-FLD) following immunoaffinity extraction (IAE). Additional analysis for LSD using the DPC Coat-a-Count RIA was performed to compare the two immunoassay screening methods. Complete agreement between the DPC RIA assay and HPLC-FLD results was observed at concentrations below a cutoff concentration of 500 pg/mL. Samples that were LSD positive in the CEDIA DAU assay but not confirmed by HPLC-FLD were also investigated for interfering compounds using REMEDI HS drug-profiling system. REMEDI HS analysis identified 15 compounds (parent drugs and metabolites) that are believed to cross-react in the CEDIA DAU LSD assay: ambroxol, prilocaine, pipamperone, diphenhydramine, metoclopramide, amitriptyline, doxepine, atracurium, bupivacaine, doxylamine, lidocaine, mepivacaine, promethazine, ranitidine, and tramadole. The IAE/HPLC-FLD combination is rapid, easy to perform and reliable. It can reduce costs when standard, rather than more advanced, HPLC equipment is used, especially for labs that perform analyses for LSD infrequently. The chromatographic analysis of LSD, nor-LSD, and iso-LSD is not influenced by any of the tested cross-reacting compounds even at a concentration of 100 ng/mL.

Ther Drug Monit. 2002 Apr;24(2):297-301.

Evaluation of REMEDi HS in the diagnosis of dimethoate poisoning.

Regenthal R, Krueger M, Trauer H, Boehm R, Preiss R.

Source

Institute of Clinical Pharmacology, Institute of Forensic Sciences, University of Leipzig, Haertelstrasse 16-18, D-04107 Leipzig, Federal Republic of Germany. regenr@medizin.uni-leipzig.de

Abstract

The authors describe the evaluation of an automated rapid emergency drug profiling system (REMEDi HS), which is designed for clinical toxicology and therapeutic drug monitoring, in a severe case of dimethoate poisoning. Successful qualitative and quantitative determination of dimethoate in diluted serum samples was achieved. The authors found that dimethoate serum concentrations were properly measured with the REMEDi method and well correlated with gas chromatography-mass spectrometry. The results provide evidence that besides screening and rapid estimation of drug concentrations in human fluids, this system is a suitable tool in cases of symptomatic dimethoate poisoning.

Forensic Sci Int. 2001 Sep 15;121(1-2):47-56.

Piperazine-like compounds: a new group of designer drugs-of-abuse on the European market.

de Boer D, Bosman IJ, Hidvégi E, Manzoni C, Benkö AA, dos Reys LJ, Maes RA.

Source

Instituto Nacional do Desporto, Laboratório de Análises de Dopagem e Bioquímica, Av. Prof. Egas Moniz (Estádio Universitário), 1600-190 Lisbon, Portugal.

Abstract

1-Aryl-piperazine compounds are, depending on their substituents, selective for certain serotonin receptors and together with their easy availability and their so-called legal status, this group of psychoactive compounds are potential designer drugs-of-abuse. Internet in that respect is an important source of information and distribution facilities. Because this development may have consequences for the interpretation of future clinical and forensic toxicological case studies, some analytical aspects of 1-benzyl-piperazine (BZP), 1-[4-methoxyphenyl]-piperazine (pMeOPP) and 1-[3-trifluoromethylphenyl]-piperazine (TFMPP) were studied. BZP was not detected by the AxSYM FPIA technology designed to determine amphetamine-like compounds, but had showed some cross reactivity with EMIT d.a.u.. The cross reactivities at 300 and 12,000ng/ml (RS)-amphetamine equivalents were 0.4 and 1.3%, respectively. Although BZP was not identified directly by the REMEDi HS Drug Profiling System, it can be detected by this HPLC/UV scanning system. Using GC/NPD without derivatisation, BZP, pMeOPP and TFMPP can be analysed for and applying GC/MS without or with acetylation or trifluoroacetylation, these compounds can be identified unambiguously. The usefulness of GC/NPD and GC/MS in this respect was demonstrated by the quantitative and qualitative analysis of the content of a capsule with the synthetic stimulant A2, which proved to contain 86.4mg of BZP.

Ther Drug Monit. 2001 Jun;23(3):287-94.

Comprehensive drug screening by integrated use of gas chromatography/mass spectrometry and Remedi HS.

Valli A, Polettini A, Papa P, Montagna M.

Source

Department of Legal Medicine and Public Health, University of Pavia, Legal Medicine and Toxicology Service, S. Matteo Hospital, Pavia, Italy.

Abstract

The authors evaluated an integrated approach for the screening of drugs in biosamples consisting of gas chromatography/mass spectrometry analysis of serum or whole blood (SB/GC-MS) and of high-performance liquid chromatographic and ultraviolet (HPLC-UV) analysis of urine with the REMEDi HS Biorad system (U/REM) (Bio-rad; Segrate, MI, Italy). Urine and blood samples from 26 suspected intoxicated patients and from 22 suspected lethal poisoning cases were examined. Eighty-one of the 99 parent drugs/main metabolites detected were identified by SB/GC-MS and 54 with U/REM. Thirty-six drugs/metabolites were identified with both methods, 45 by SB/GC-MS alone, and 18 by U/REM alone. Absence of the mass spectrometry (MS) spectra in the reference library and high polarity of the analytes were the main reasons for failed identification by SB/GC-MS. Unsuccessful identifications with U/REM were basically caused by the absence of the UV spectra in the reference library or by low chromatographic and spectroscopic selectivity as in the case of barbiturates and benzodiazepines (BZD), which represented 11% and 51%, respectively, of the 45 SB/GC-MS unique identifications. Urine samples of 14 BZD-positive cases were also submitted to enzymatic hydrolysis and analyzed with the REMEDi UBz assay, and results were compared with those obtained by SB/GC-MS: 14 of the 22 identified BZD were detected with both methods, three by U/REM only, and five by SB/GC-MS only. In conclusion, the integrated use of SB/GC-MS and U/REM approaches greatly enhances the amount and quality of analytical information obtainable by applying either method alone.

PMID:

11360040

[PubMed – indexed for MEDLINE]

 

J Forensic Sci. 2000 Nov;45(6):1327-31.

Screening of amphetamine/methamphetamine and their derivatives in urine using FPIA and Triage 8 and the Scope and limits of a subsequent identification by means of the REMEDi HS system.

Felscher D, Schulz K.

Source

Faculty of Medicine, Carl Gustav Carus of the Technical University of Dresden Institute of Forensic Medicine, Germany.

Abstract

This study describes screening and identifying amphetamines, methamphetamines, and their derivatives in urine using immunochemical (Triage, FPIA) and chromatographic techniques (REMEDi HS). Amphetamines, methamphetamines, MDMA (3,4-methylenedioxymethamphetamine), MDA (3,4-methylenedioxyamphetamine), MDE (3,4-methylenedioxyethyl-amphetainine), MBDB (N-methyl-1-(3,4-methylenedioxyphenyl)-2-butanamine), BDB (3,4-(methylenedioxyphenyl)-2-butanamine), PMA (4-methoxyamphetamine), DOM (2,5-dimethyloxy-4-methylamphetamine), DOB (4-bromo-2,5-dimethyloxyamphetamine), amphetaminil, pholedrine, fenfluramine, and amfepramone were subjected to a comparative study. For this, the substances were analyzed to determine their specific threshold concentration for a positive detection in the Triage test and their limit of detection and positive threshold concentration for the FPIA test and the results compared. Furthermore, the capabilities of a more detailed analysis with the REMEDi system were studied. This HPLC system was able to produce information on the single drugs and main metabolites found in the sample with the danger of false-positive or false-negative screening results greatly minimized.

Forensic Sci Int. 2000 Sep 11;113(1-3):403-7.

Detection of psilocin in body fluids.

Sticht G, Käferstein H.

Source

Institute of Forensic Medicine, University of Cologne, Melatengürtel 60-62, D-50823, Köln, Germany.

Abstract

Active compounds of some mushrooms e.g. Psilocybe cubensis, Paneolus subalteatus or Stropharia coronilla, the psychotropic agents psilocybin and psilocin, have hallucinogenic effects. In one case of ‘magic mushroom’ intake, we had to analyse blood and urine. Psilocin was detected in the urine with REMEDi HS. Most of the psilocin was excreted as the glucuronide. Therefore an enzymatic hydrolysis should be the first step in analysis. Free psilocin was determined at a concentration of 0.23 mg/l while the total amount was 1.76 mg/l urine. The concentration of psilocin in serum was too low for detection with REMEDi HS. We proved a GC-MS-method with d(3)-morphine as internal standard and silylation with MSTFA. Similarly to urine, most of the psilocin in serum was found in the conjugated form. The concentration of free psilocin was 0.018 mg/l, that of total psilocin, 0.052 mg/l serum.

PMID:

10978655

[PubMed – indexed for MEDLINE]

 

Ann Biol Clin (Paris). 1999 Sep-Oct;57(5):525-37.

[Critical analysis of different methods used for toxicology screening in emergency laboratory].

[Article in French]

Pechard A, Besson AS, Mialon A, Berny C, Manchon M.

Source

Laboratoire des urgences biochimiques et toxicologiques, Centre hospitalier Lyon-Sud, 69495 Pierre-Bénite Cedex.

Abstract

Emergency analysis in toxicology is a difficult exercise. It involves in diagnosis, prognosis and the treatment of intoxication. Several methods exist in emergency screening. We have distinguished three large groups. Based on specificity: screening methods of medicament family (chemical methods and immunoassays) with benzodiazepines, tricyclic antidepressants, barbiturates and phenothiazines; complementary screening methods (thin layer chromatography and high pressure liquid chromatography) for a wider screening and finally quantitative methods (enzymatic, immunoassay, spectrometry and chromatography) specific to a molecule. The first group allows a rapid qualitative research according to medicament class but lacks specificity. The second group represented by the Remedi system, offers a larger screening of molecules but is more expensive and cannot detect classic molecules. The third group allows a precise dosage but is restricted to one molecule. We need one or the other of methods following clinical context and the type of molecule. In our laboratory, we have eliminated barbiturates and benzodiazepines research. We search only tricyclic antidepressants, salicylates and paracetamol. The Remedi system acts as a complement. It is essential to have a good knowledge of the limits and specificity of each method in order to allow the clinician to see the interpretation of the given result. The execution period and the quality of analytical result depend on dialogue between analyst and clinician before and after analysis.

PMID:

10518054

[PubMed – indexed for MEDLINE]

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Clin Chem. 1999 Aug;45(8 Pt 1):1224-34.

Broad spectrum drug identification directly from urine, using liquid chromatography-tandem mass spectrometry.

Fitzgerald RL, Rivera JD, Herold DA.

Source

Veterans Administration Medical Center San Diego and University of California San Diego, 3350 La Jolla Village Dr., San Diego, CA 92161, USA.

Abstract

BACKGROUND:

Currently the rate-limiting step for mass spectrometric analysis of drugs in biological samples is sample preparation. Many gas chromatography/mass spectrometry (GC/MS) methods are specific for a certain class of compounds, requiring extraction and/or derivatization before analysis. The purpose of this study was to develop a broad spectrum liquid chromatography/mass spectrometry (LC/MS) procedure that allowed for direct analysis of urine specimens with potential for quantitative analysis.

METHODS:

We modified a commercially available column-switching instrument, the REMEDi HS from Bio-Rad Diagnostics, to make it compatible with atmospheric pressure ionization. The system we developed was based on electrospray ionization and used three LC columns to extract, purify, and separate drugs directly from urine specimens. Drugs and metabolites were tentatively identified on the basis of retention times and (M+H)(+) ions. Tandem mass spectrometry (MS/MS) was used to confirm the qualitative identification of suspected drugs, using data-dependent acquisition. For quantitative analysis, the cocaine metabolite benzoylecgonine was analyzed using isotope dilution and selected reaction monitoring.

RESULTS:

Seventeen basic drugs from a variety of classes of compounds were identified directly from urine without the need for prior sample extraction, using LC and MS/MS. Quantitative analysis was demonstrated for benzoylecgonine. When benzoylecgonine-d(3) was used as the internal standard, the method was linear from 30 to 10 000 microgram/L (range tested). At these concentrations, the within-run accuracy was +/- 10% of the target concentration, with CVs <10%. Analytical results by LC/MS/MS compared favorably with GC/MS values for 50 benzoylecgonine-containing specimens and for 25 negative specimens.

CONCLUSIONS:

The ability to directly analyze urine for a wide variety of drug classes, combined with the sensitivity and specificity of LC/MS/MS makes this technique attractive for many clinical, forensic, and biotechnology applications.

PMID:

10430788

[PubMed – indexed for MEDLINE]

Free full text

J Clin Lab Anal. 1999;13(3):106-11.

Determination of benzodiazepines in clinical serum samples: comparative evaluation of REMEDi system, aca analyzer, and conventional HPLC performance.

Chang TL, Chen KW, Lee YD, Fan K.

Source

Department of Pathology, National Cheng Kung University Hospital, Tainan, Taiwan, ROC. tsuiling@mail.ncku.edu.tw

Abstract

Emergency toxicology or drug screening in clinical settings requires rapid qualitative and quantitative analysis with acceptable levels of sensitivity and specificity. The aim of this study was to comparatively evaluate the performance of the multi-column HPLC-based REMEDi drug profiling system (Bio-Rad), the aca analyzer (Du Pont), and the bench standard conventional HPLC method in the identification of 12 clinically important benzodiazepines. In this study, the presence of benzodiazepines in 133 patients’ serum samples were qualitatively and comparatively analyzed by these three procedures. Among these methods, 120 of 133 samples were identified as benzodiazepine-positive by conventional HPLC (90%); 127 by aca analyzer (95%); and 84 by REMEDi (63%). Detection sensitivity of REMEDi for most of the benzodiazepines was found satisfactory when concentrations were greater than 1.0 microg/mL. When benzodiazepine concentrations were in the ranges of 0.3-1.0 microg/mL, detection sensitivity became varied among the benzodiazepine family of drugs by REMEDi method. REMEDi procedure should not be considered as the method of choice for detection of benzodiazepines if expected concentration levels are below 0.3 microg/mL, with the exception of bromazepam. Conventional HPLC displayed the highest sensitivity and specificity for the detection of benzodiazepines. In our studies, 36 REMEDi-negative samples were positive by HPLC, although in 16 of the 36 REMEDi negative samples (13.3%), the presence of benzodiazepines was detected but only listed as candidates without positive identification of the individual compounds by REMEDi. In our series, however, there were no false positives by the REMEDi method whereas aca procedure showed 13 false positive results (9%) and 6 cases of false negative (4%). Our data indicate that the REMEDi procedure can be used on serum samples for rapid qualitative screening of clinically important high levels of benzodiazepines with high specificity. However, due to the relatively low sensitivity of REMEDi in samples with low benzodiazepine levels and relatively low specificity by aca, all samples should be further confirmed by conventional HPLC procedure.

PMID:

10323474

[PubMed – indexed for MEDLINE]

 

Clin Chem Lab Med. 1998 Oct;36(10):803-8.

First experience with the REMEDi HS urine benzodiazepine assay.

Musshoff F, Madea B.

Source

Institut für Rechtsmedizin, Rheinische Friedrich-Wilhelms-Universität, Bonn, Germany.

Abstract

Ninety eight urine samples were analysed with an immunoassay benzodiazepine kit. A total of 68 urine specimens that were presumptively positive for benzodiazepines were evaluated by the REMEDi HS urine benzodiazepine assay (BIO-RAD, Munich, Germany). Of this number, 53 (78%) specimens were found by REMEDi to contain one or more benzodiazepines or their metabolites, and 15 (22%) were found to be negative. From the discordant group of 15 samples, eight were found to be negative using conventional chromatographic procedures (HPLC or GC/MS), while seven contained one or more benzodiazepines or metabolites, each of which were below the individual cut-off level specified by the manufacturer. Additionally 30 urine specimens that were negative for benzodiazepines using immunoassay were also tested by REMEDi. Two samples were found to be positive. These results could not be confirmed by other chromatographic techniques. The REMEDi HS benzodiazepine assay can be a very useful complementary technique in the clinical/forensic toxicology laboratory, especially for the identification of the parent benzodiazepines administered. The assay provides a rapid result in emergency situations and is useful in confirmation of preliminary positive immunoassay results.

Tex Med. 1997 Sep;93(9):50-8.

Drugs detected in patients suspected of acute intoxication.

Baskin LB, Morgan DL.

Source

Department of Pathology, University of Texas Southwestern Medical Center, Dallas 75235-9072, USA.

Abstract

Drug screens were performed for 434 adult patients who presented to the Parkland Memorial Hospital Emergency Department with suspected acute drug overdose. The screening consisted of analysis of urine by automated high performance liquid chromatography (REMEDi) in combination with qualitative EMIT immunoassays. Selected patients also had ethanol measured in blood, salicylate and acetaminophen measured in serum, and urine specimens analyzed qualitatively for cannabinoids. Most patients (83.4%), regardless of age, race, or gender, had evidence of consumption of at least one drug. The drugs detected most often were ethanol (30.0%) and cocaine (23.7%). At least one of the nine most common drugs-of-abuse (amphetamines, barbiturates, benzodiazepines, cannabinoids, cocaine, ethanol, opiates, opioids, and phencyclidine) was detected in 64.5% of the specimens, and combinations of these drugs were present in 45.4%. For most drugs, age, gender, ethnicity, time of day, day of week, and indication for screening could not be used to predict the drug screen result.

PMID:

9754396

[PubMed – indexed for MEDLINE]

 

 

Nihon Hoigaku Zasshi. 1997 Jun;51(3):235-40.

False identification of urinary ephedrine as methamphetamine by gas chromatography/mass spectrometry with a DB-17 column.

Takayasu T, Ohshima T, Ohtsuji M, Takayama N, Kondo T, Lin Z, Sato Y, Minamino T.

Source

Department of Legal Medicine, Kanazawa University Faculty of Medicine, School of Medicine, Japan.

Abstract

A 17-year-old motorcyclist was killed in a traffic accident. The urine sample collected at autopsy was screened by the Toxi-Lab system; it showed a possible presence of either methamphetamine (MA) or ephedrine (Eph). Gas chromatography-mass spectrometry (GC-MS) was carried out for a trifluoroacetyl (TFA)-derivatized sample after extraction with an Extrelut column. A peak was detected at the same retention time as that of the authentic Eph by GC-MS with a DB-17 wide-bore column; the mass spectrum of the peak was, however, very similar to that of MA. The presence of Eph and absence of MA were proved by GC-MS using a DB-1 column. The Eph in the urine was further confirmed by high performance liquid chromatography (HPLC)-MS using an ODS column. By the REMEDi HS system, Eph and methylephedrine were determined in the urine, and their concentrations (hydrochloride salt) were 0.752 and 2.13 micrograms/ml, respectively. Ethanol was detected as well in the blood (1.55 mg/ml) and urine (2.01 mg/ml) by a pulse heating method. Nicotine, caffeine and dihydrocodeine were also qualitatively detected in the urine by Toxi-Lab, HPLC-MS and REMEDi HS systems. The present case warned that urinary Eph can be misidentified as MA by GC-MS with an intermediately polar column after TFA derivatization

 

Ann Biol Clin (Paris). 1997 May-Jun;55(3):223-8.

[Value of the Remedi chromatography automate for the analytic diagnosis of drug poisoning].

[Article in French]

Manchon M, Mialon A, Berny C, Baltassat P.

Source

Laboratoire des urgences biochimiques et toxicologiques, Pierre-Bénite.

Abstract

The aim of this study was to evaluate the liquid chromatographic system Remedi (Biorad) in comparison with traditional immunological and colorimetric methods, for the diagnosis of acute drug overdose. 469 blood samples and 95 stomach cleaning liquid samples have been analysed during 1995. The usual toxicologic analysis was composed of the benzodiazepines, tricyclic antidepressants and barbiturates research. Ethanol, meprobamate and acetaminophen assays were performed only on physician’s request. Only three pharmacological classes can be analysed both with immunological methods and Remedi: benzodiazepines, tricyclic antidepressants and barbiturates. Remedi has been found to be less sensitive than immunological method for benzodiazepines, it sometimes gave false negative results for barbiturates, but it was very efficient for antidepressants. Remedi often identified drugs other than the 3 previous classes: sedatives, antipsychotic, beta-blockers, antiarythmics. Furthermore these drugs are of clinical importance due to the fact that they are able to modify the symptomatology. In every case Remedi was able to give an estimation of the blood concentration of the toxic molecule matched. Remedi can not replace traditional methods but is a good complementary tool, available in emergency. This is particularly useful when clinical signs do not correspond to the toxics suspected by questioning the patient or relatives.

Clin Chem. 1997 Mar;43(3):498-504.

Automated liquid-chromatographic analyzer used for toxicology screening in a general hospital: 12 months’ experience.

Sadeg N, François G, Petit B, Dutertre-Catella H, Dumontet M.

Source

Laboratoire Claude Bernard Hôpital de Pontoise, France.

Abstract

We evaluated the clinical utility of an automated HPLC system (Remedi, Bio-Rad) for identification of drugs and metabolites in biological fluids. Serum or urine or both from 354 consecutive cases of poisoning were analyzed by the system and by a set of fluorescence polarization immunoassay (FPIA, Abbott) and thin-layer chromatographic (TLC) procedures. Antidepressants and most phenothiazines were recognized by the new system. Comparison of Remedi results with final clinical diagnoses yielded diagnostic specificity and sensitivity of 80% and 90%, respectively. Remedi detected 26 additional compounds that were neither reactive in the immunoassay screening tests nor detected by TLC procedures. Because the Remedi expands the range of drugs covered by the immunoassays and provides a rapid, preliminary report in emergency situations, we conclude that this system can be a useful complementary technique in the clinical toxicology laboratory. Although urine toxicological screening seemed adequate for a good toxicological report, blood analysis allows extra toxicokinetic data such as blood concentrations and half-life estimations.

PMID:

9068594

[PubMed – indexed for MEDLINE]

Free full text

J Anal Toxicol. 1996 Oct;20(6):416-24.

Identification of urinary benzodiazepines and their metabolites: comparison of automated HPLC and GC-MS after immunoassay screening of clinical specimens.

Valentine JL, Middleton R, Sparks C.

Source

Department of Pediatrics, University of Arkansas for Medical Sciences and Toxicology Laboratory of Arkansas Children’s Hospital, Little Rock 72202-3591, USA.

Abstract

An automated high-performance liquid chromatographic method, benzodiazepines by REMEDi HS, was used to analyze benzodiazepines and their metabolites after beta-glucuronidase hydrolysis of 1-mL urine specimens from the following: 924 clinic and hospital patients whose specimens had previously been found to be presumptively positive using either EMIT or Triage immunoassay methodologies and 128 individuals whose specimens had screened negative by EMIT d.a.u.TM. REMEDi analyses did not correlate with the immunoassay results in 136 of the positive and three of the negative urine specimens. Gas chromatographic-mass spectrometric (GC-MS) confirmatory analyses were performed on these discordant specimens using 3 mL beta-glucuronidase-hydrolyzed urine followed by extraction with chloroform-isopropanol (9:1) and derivatization with N,O-bis(trimethylsilyl)trifluoroacetamide. Two benzodiazepines, flunitrazepam and clonazepam, and their 7-amino metabolites were analyzed without prior derivatization. The analyses established 87% concordance between REMEDi and GC-MS versus 13% concordance with immunoassay for the subset. GC-MS analysis of these 142 specimens demonstrated two reasons for the nonconcurrence between REMEDi and EMIT: EMIT had given either false-negative or false-positive results and EMIT had given a positive result even though the determined metabolites were below the 200-ng/mL cutoff for the immunoassay and the 80-ng/mL cutoff for REMEDi. A total of 23 specimens were found to contain only lorazepam by REMEDi and GC-MS, 15 of which had been screened by Triage. A reevaluation of these 23 specimens by EMIT d.a.u. demonstrated that 11 were positive. This finding was in contrast to previous reports that EMIT will not detect lorazepam glucuronide in urine. An unexpected finding was the REMEDi identification and subsequent GC-MS confirmation of 7-aminoflunitrazepam, a urinary metabolite of flunitrazepam that is not available in the United States and that represented illicit use by four patients. A distinct advantage of REMEDi proved to be its capability in identifying demoxepam, a major metabolite of chlordiazepoxide; GC-MS analysis could not detect this metabolite because of its thermal decomposition to nordiazepam. To further evaluate the specificity of REMEDi, we conducted GC-MS analyses in a random fashion on 55 additional nondiscordant urine specimens that were identified as either positive or negative, as well as 22 specimens identified as containing 7-aminoclonazepam by REMEDi. Concurrence was observed between the two methods for all specimens, with the exception of one apparent false positive for alpha-hydroxyalprazolam by REMEDi. The reproducibility of the REMEDi method was found to be excellent; it was assessed by comparing results of 266 specimens that were reprocessed in different batches and for known calibrators and controls also processed with each batch. Study results demonstrated that the automated REMEDi assay for urinary benzodiazepines and their metabolites was comparable with GC-MS but had distinct advantages over GC-MS because of the following reasons: simplicity of the assay, less time required for analyses, and provision of additional information concerning the parent benzodiazepine.

J Forensic Sci. 1996 Sep;41(5):881-6.

Use of REMEDi HS in emergency toxicology for a rapid estimate of drug concentrations in urine, serum, and gastric samples.

Ohtsuji M, Lai JS, Binder SR, Kondo T, Takayasu T, Ohshima T.

Source

Department of Legal Medicine, Kanazawa University, Faculty of Medicine, Japan.

Abstract

The REMEDi HS is a broad spectrum drug identification system, designed for emergency toxicology screening and forensic applications. The total analysis time is about 20 min. The current library has 555 drugs and metabolites. The system has a software routine that uses an internal standard (IS) to perform quantitative analysis for target compounds when calibrators are available; further, response factors (RF) are supplied for a rapid estimate of drug concentrations when calibrators are unavailable. In the present study, The concentrations of six drugs (bromisovalum, ephedrine, hydroxyzine, diphenhydramine, ranitidine, and lidocaine) and a metabolite of lidocaine (glycinexylidide) were determined using both methods. The slopes of the regression lines between the rapid estimate method and the IS method were generally within 20% of unity, in agreement with the manufacturer’s claim. Semiquantitative estimates based on RF also showed good agreement with results obtained using multipoint calibration. These estimates were sufficient for clinical differentiation of routine and toxic levels. Our study demonstrated that the REMEDi HS is particularly useful for a rapid estimate of drug concentrations in the samples from emergency cases when calibrators are not readily available. Our study also showed that this system can be used for the therapeutic monitoring of ranitidine, bromisovalum, lidocaine, and diphenhydrmine.

J Chromatogr B Biomed Appl. 1996 Aug 30;683(2):199-208.

Use of direct-probe mass spectrometry as a toxicology confirmation method for demoxepam in urine following high-performance liquid chromatography.

Essien H, Lai SJ, Binder SR, King DL.

Source

Clincal Systems Division, Bio-Rad Laboratories, Hercules, CA 94547, USA.

Abstract

The identification of the metabolite demoxepam in human urine establishes that chlordiazepoxide, a common benzodiazepine, has been administered. Like N-oxide metabolites of other drugs, demoxepam cannot be detected by gas chromatography-mass spectrometry (GC-MS), due to thermal decomposition, and the product, nordiazepam, is a metabolite common to many benzodiazepines. Demoxepam can be readily screened using a high-performance liquid chromatography (HPLC) system such as REMEDi HS; at 35 degrees C, no thermal decomposition will occur. Currently, there is no confirmation method available for the detection of demoxepam in urine samples. In this study, we demonstrated that following collection of the HPLC fraction, demoxepam can be confirmed using the technique of direct-probe MS. The mass spectra of demoxepam and nordiazepam differ and are easily distinguishable from each other. Ten urine samples that were analyzed by HPLC and determined to contain demoxepam were evaluated; demoxepam was confirmed in each case by direct-probe MS.

Przegl Lek. 1996;53(4):377-9.

The use of REMEDI HS in toxicological diagnostics of patients poisoned with drugs at the Department of Toxicology Collegium Medicum of the Jagiellonian University in Kraków.

Pach J, Panas M, Sołtycka M, Wilimowska J.

Source

Department of Toxicology, Collegium Medicum, Jagiellonian University, Kraków.

 

J Anal Toxicol. 1995 Oct;19(6):412-8.

Forensic application of an automated drug-profiling system.

Kalasinsky KS, Schaefer T, Binder SR.

Source

Division of Forensic Toxicology, Armed Forces Institute of Pathology, Washington, DC 20306-6000, USA.

Abstract

The rapid emergency drug identification (REMEDi) system is an automated drug-profiling system that employs high-performance liquid chromatography with a multicolumn design. It has previously proven successful in emergency toxicology situations and in the clinical analysis of urine and serum. Its capabilities include the broad spectrum identification of more than 500 basic, neutral, and slightly acidic drugs and metabolites. Forensic applications, including analysis of whole blood and tissue, were investigated, and comparisons with more traditional laboratory methods are reported. The whole blood and tissue samples require offline sample extraction prior to system analysis. Approximately 50 drugs were used as standards to test the preparation method, analytical system, and limit of detection. More than 50 cases from the medical examiner’s office were analyzed with the combination extraction and automated drug-profiling system; these cases were compared with previously reported findings. Results showed that the REMEDi system is a useful complimentary tool for screening forensic cases; the current range of detectable drugs was expanded by using the system.

PMID:

8926735

[PubMed – indexed for MEDLINE]

J Toxicol Clin Toxicol. 1995;33(6):581-9.

The development of a broad-spectrum toxicology screening program in Taiwan.

Chen JS, Chang KJ, Charng RC, Lai SJ, Binder SR, Essien H.

Source

Department of Clinical Pathology, Taipei Institute of Pathology, Taiwan, R.O.C.

Abstract

Our institute serves as a centralized clinical laboratory for municipal and private hospitals in Taipei, a major international metropolis in the Asian region. Two key considerations leading to the development of our toxicology program are: a large number of foreign visitors and local residents returning from overseas trips may bring in chemicals which are less commonly seen in this region; and the lack of readily available assays for a large percentage of commonly used medicines, including prescription and over-the-counter drugs. Our toxicology screening program addresses the needs of both the Emergency Department Drug Screening and Drug of Abuse Screening. In Emergency Department Drug Screening, REMEDi HS is used as the general screening method. In Drug of Abuse Screening, the TDx is used for the initial screening of amphetamine-like substances and opiates, followed by REMEDi HS for the confirmation of positive samples. Emergency Department data collected at our institute over one year (September 1992 to August 1993) identified 57 different drugs in 713 samples. Opiates, narcotics and central stimulants accounted for 24% of the encountered drugs. Presently, there is no extensive reporting of misuse of benzodiazepines in this region. The detection of herbal ingredients like ephedrine and methylephedrine (from the Ma-Huang plant) in patient samples illustrates a large area often overlooked by western toxicology.

J Anal Toxicol. 1994 Sep;18(5):278-91.

Drugs-of-abuse testing in urine: statistical approach and experimental comparison of immunochemical and chromatographic techniques.

Ferrara SD, Tedeschi L, Frison G, Brusini G, Castagna F, Bernardelli B, Soregaroli D.

Source

Centre of Behavioural and Forensic Toxicology, University of Padova, Italy.

Abstract

This study deals with the experimental and statistical comparison of six immunochemical techniques, including noninstrumental on-site and instrumental formats (EIA-EMIT and EZ-SCREEN; FPIA-ADx; RIA-Coat-A-Count; LI-Abuscreen ONTRAK; CBI-Triage), and three chromatographic techniques (TLC-Toxi-Lab; HPLC; HPLC-REMEDi drug profiling system), using GC-MS as a reference technique for analyzing amphetamines, barbiturates, benzodiazepines, cannabinoids, cocaine, methadone, and opiates in the urine of various kinds of drug users. The study reports (a) the values of sensitivity, specificity, false-positive rates, and false-negative rates of each technique; (b) the results of bayesian statistical analysis, which are based on prevalence values of the samples examined and expressed as positive and negative predictive values and cumulative predictive values for each single technique and for combinations of paired immunochemical and chromatographic techniques; and (c) the results of a rough classification of the various degrees of predictability of these techniques. Lastly, this study proposes a decision-making process for establishing the best combination of analytical techniques for the goals in question, according to the characteristics and facilities of each laboratory.

Eur J Clin Chem Clin Biochem. 1994 May;32(5):409-17.

Evaluation of the REMEDi drug profiling system.

Demedts P, Wauters A, Franck F, Neels H.

Source

A. Z. Middelheim, Laboratorium voor Klinische Scheikunde en Toxicologie, Antwerpen, Belgium.

Abstract

One hundred and sixteen samples for toxicological analysis (78 urines and 38 stomach contents) were analysed both with the Bio-Rad REMEDi Drug Profiling System and with a set of immunoassays and standard chromatographic procedures (HPLC, GC/NPD and GC/MS). As a screening method, REMEDi performed only moderately well, compared with immunoassays. Amphetamines and tricyclic antidepressants were detected by REMEDi in 80% and 68%, respectively, of the positive immunoassay results. Positive immunoassay screening tests were more often confirmed by the conventional chromatographic methods (80%) than by REMEDi (35%). The highest confirmation score for REMEDi was observed in the amphetamine group (9 of 12), while low scores were obtained for barbiturates (1 of 7) and benzodiazepines (13 of 75). However, in these samples REMEDi detected 53 additional compounds, which were neither reactive in the immunoassay screening tests, nor detected by the standard chromatographic procedures. These results clearly demonstrate that REMEDi can be a useful complementary technique in the clinical toxicology laboratory, since it expands the range of drugs covered by the immunoassays and provides a rapid, preliminary report in emergency situations.

Ann Biol Clin (Paris). 1994;52(2):111-5.

Development of a solid/liquid extraction method for analysis of toxic drugs in serum using an automated liquid chromatograph: the Remedi.

Guitton J, Durand D, Bouillod N, Manchon M.

Source

Laboratoire des Urgences Biochimiques et Toxicologiques, Service de Biochimie (MP Baltassat), Hôpital Jules-Courmont, Centre Hospitalier Lyon Sud, Pierre Bénite, France.

Abstract

The aim of this work was to develop a procedure for analysis of drugs in serum using a chromatographic apparatus marketed by the Bio-Rad company. This automated apparatus, the Remedi, can identify nearly 200 substances and metabolites in biological fluids. The method for pretreatment of serum recommended by the manufacturer is inefficient. We thus decided to develop and validate an extraction method for analysis of serum. Our method extends column life and improves the sensitivity of the Remedi for the detection of drugs. For psychotropic drugs, a study was carried out that enables a semi-quantitative evaluation of blood levels to be made. In addition, the sera of patients admitted to hospital for intentional drug overdosage were studied to compare the results obtained using the Remedi and Emit techniques, and also to compare these results with toxicological data obtained by questioning the patient and his immediate circle.

Clin Chem. 1992 Nov;38(11):2349-50.

REMEDi drug profiling system readily distinguishes between cyclobenzaprine and amitriptyline in emergency toxicology urine specimens.

Poklis A, Edinboro LE.

PMID:

1424145

[PubMed – indexed for MEDLINE]

Free full text

Biomed Chromatogr. 1991 Nov;5(6):269-72.

Disopyramide analysis using REMEDi: comparison with EMIT and conventional high performance liquid chromatographic methods.

Patel V, McCarthy PT, Flanagan RJ.

Source

Poisons Unit, Guy’s Hospital, London, UK.

Abstract

REMEDi (Rapid EMErgency Drug identification; Bio-Rad) is an automated high performance liquid chromatographic (HPLC) system designed to detect, identify and measure a range of basic and neutral drugs in 0.5-1.0 mL of urine or plasma/serum. We have evaluated REMEDi in the analysis of the antiarrhythmic drug disopyramide in patient samples. The specimens were also analysed by a conventional HPLC method, based on solvent extraction and UV detection (254 nm), and by EMIT. There were good correlations between the results obtained with each method (r = 0.91 or greater). REMEDi gave a lower mean result than EMIT [means +/- SD (mg/L): REMEDi 2.64 +/- 1.10, EMIT 3.14 +/- 1.51; t = 4.0, p less than 0.01; n = 25], but there were no other significant differences in mean results. The principal disopyramide metabolite, mono-N-desalkyldisopyramide, did not interfere in any method. Clearly REMEDi can be used for therapeutic drug monitoring of disopyramide provided enough sample is available.

J Anal Toxicol. 1995 Oct;19(6):412-8.

Forensic application of an automated drug-profiling system.

Kalasinsky KS, Schaefer T, Binder SR.

Source

Division of Forensic Toxicology, Armed Forces Institute of Pathology, Washington, DC 20306-6000, USA.

Abstract

The rapid emergency drug identification (REMEDi) system is an automated drug-profiling system that employs high-performance liquid chromatography with a multicolumn design. It has previously proven successful in emergency toxicology situations and in the clinical analysis of urine and serum. Its capabilities include the broad spectrum identification of more than 500 basic, neutral, and slightly acidic drugs and metabolites. Forensic applications, including analysis of whole blood and tissue, were investigated, and comparisons with more traditional laboratory methods are reported. The whole blood and tissue samples require offline sample extraction prior to system analysis. Approximately 50 drugs were used as standards to test the preparation method, analytical system, and limit of detection. More than 50 cases from the medical examiner’s office were analyzed with the combination extraction and automated drug-profiling system; these cases were compared with previously reported findings. Results showed that the REMEDi system is a useful complimentary tool for screening forensic cases; the current range of detectable drugs was expanded by using the system.

Eur J Clin Chem Clin Biochem. 1994 May;32(5):409-17.

Evaluation of the REMEDi drug profiling system.

Demedts P, Wauters A, Franck F, Neels H.

Source

A. Z. Middelheim, Laboratorium voor Klinische Scheikunde en Toxicologie, Antwerpen, Belgium.

Abstract

One hundred and sixteen samples for toxicological analysis (78 urines and 38 stomach contents) were analysed both with the Bio-Rad REMEDi Drug Profiling System and with a set of immunoassays and standard chromatographic procedures (HPLC, GC/NPD and GC/MS). As a screening method, REMEDi performed only moderately well, compared with immunoassays. Amphetamines and tricyclic antidepressants were detected by REMEDi in 80% and 68%, respectively, of the positive immunoassay results. Positive immunoassay screening tests were more often confirmed by the conventional chromatographic methods (80%) than by REMEDi (35%). The highest confirmation score for REMEDi was observed in the amphetamine group (9 of 12), while low scores were obtained for barbiturates (1 of 7) and benzodiazepines (13 of 75). However, in these samples REMEDi detected 53 additional compounds, which were neither reactive in the immunoassay screening tests, nor detected by the standard chromatographic procedures. These results clearly demonstrate that REMEDi can be a useful complementary technique in the clinical toxicology laboratory, since it expands the range of drugs covered by the immunoassays and provides a rapid, preliminary report in emergency situations.

lin Chem. 1997 Mar;43(3):498-504.

Automated liquid-chromatographic analyzer used for toxicology screening in a general hospital: 12 months’ experience.

Sadeg N, François G, Petit B, Dutertre-Catella H, Dumontet M.

Source

Laboratoire Claude Bernard Hôpital de Pontoise, France.

Abstract

We evaluated the clinical utility of an automated HPLC system (Remedi, Bio-Rad) for identification of drugs and metabolites in biological fluids. Serum or urine or both from 354 consecutive cases of poisoning were analyzed by the system and by a set of fluorescence polarization immunoassay (FPIA, Abbott) and thin-layer chromatographic (TLC) procedures. Antidepressants and most phenothiazines were recognized by the new system. Comparison of Remedi results with final clinical diagnoses yielded diagnostic specificity and sensitivity of 80% and 90%, respectively. Remedi detected 26 additional compounds that were neither reactive in the immunoassay screening tests nor detected by TLC procedures. Because the Remedi expands the range of drugs covered by the immunoassays and provides a rapid, preliminary report in emergency situations, we conclude that this system can be a useful complementary technique in the clinical toxicology laboratory. Although urine toxicological screening seemed adequate for a good toxicological report, blood analysis allows extra toxicokinetic data such as blood concentrations and half-life estimations.