Facile synthesis of copper(II) oxide nanospheres covered on functionalized multiwalled carbon nanotubes modified electrode as rapid electrochemical sensing platform for super-sensitive detection of antibiotic

Herein, we report a super-active electrocatalyst of copper(II) oxide nanoparticles (CuO NPs) decorated functionalized multiwalled carbon nanotubes (CuO NPs@f-MWCNTs) by the ultrasonic method. The as-synthesized CuO NPs@f-MWCNTs was characterized through the FESEM, XPS, XRD and electrochemical impedance spectroscopy (EIS). The combination of highly active CuO NPs and highly conductive f-MWCNTs film with rapid detection enables this nanohybrid to display excellent electrochemical performance towards anesthesia drug. Furthermore, the hybrid electrocatalyst modified SPCE was developed for the determination of flunitrazepam (FTM) for the first time. FTM is important anesthesia drug with high adverse effect in human body. Benefiting from the synergistic reaction of CuO NPs and f-MWCNTs, this nanohybrid exhibited high sensitivity and specificity towards FTM electro-reduction. The CuO NPs@f-MWCNTs film modified SPCE exhibits outstanding electrochemical activity including excellent reproducibility, wide linear range from 0.05 to 346.6 µM with nanomolar limit of detection for FTM detection. Further, the as-modified CuO NPs@f-MWCNTs/SPCE has been applied to determination of FTM in biological and drug samples with satisfactory recovery results, thereby showing a notable potential for extensive (bio) sensor applications.

Production of monoclonal antibody against clonazepam for immunoassay of benzodiazepine drugs in swine tissues

The objective of the present study was to produce a generic monoclonal antibody for immunoassay of residues of benzodiazepine drugs in swine tissues. Clonazepam was used to synthesize a hapten that was coupled to bovine serum albumin as an immunogen for the production of monoclonal antibody. Results showed that the obtained monoclonal antibody was able to recognize five benzodiazepine drugs simultaneously (clonazepam, flunitrazepam nitrazepam, diazepam, and oxazepam). The cross-reactivities were in the range of 24-100% and the limits of detection were in the range of 0.2-1.5 ng mL(-1) depending on the drug. Then a competitive indirect enzyme-linked immunosorbent assay was developed to determine the residues of five benzodiazepines in swine tissues (muscle, liver and kidney). The recoveries of five analytes from the fortified blank samples were in the range of 74.5-96.5% with coefficients of variation lower than 16.7%. Therefore, this immunoassay could be used as a rapid and simple method for the screening of residues of five benzodiazepine drugs in animal-derived foods.

A case of drowning whilst under the influence of brotizolam, flunitrazepam and ethanol

A case of drowning involving brotizolam, flunitrazepam and ethanol ingestion was presented. Quantitative toxicological analysis showed that the concentrations of brotizolam, 7-aminoflunitrazepam (a metabolite of flunitrazepam) and ethanol in the femoral blood were 0.025 microg/ml, 0.094 microg/ml and 0.29 mg/ml, respectively, and these drugs were also detected in the stomach contents. We concluded that the cause of death was drowning whilst under the influence of combined use of brotizolam, flunitrazepam and ethanol.

[Analysis of the binding capacity of the benzodiazepine site of gabaa receptor in mice C57BL/6 and BALB/C pretreated with anxiolytics]

The level of specific 3H-flunitrazepam binding in synaptosomal membranes of C57BL/6 and BALB/c mice brain underwent to the stress of different types has been studied. Mild stress (Elevated Plus Maze) was shown to induce the decrease of benzodiazepine binding in BALB/c mice only, while the strong one (Exposure to a predator) was revealed to cause this decrease in both strains. Behavioral effects of different non-benzodiazepine drugs possessing anxiolytic properties (Afobazol, Ladasten and Noopept) was accompanied with the normalization of the level of benzodiazepine reception, reduced by the stress of both modalities.

The detection of various opiates and benzodiazepines by comprehensive two-dimensional gas chromatography/time-of-flight mass spectrometry

A technique using comprehensive two-dimensional gas chromatography/time-of-flight mass spectrometry (GC x GC/TOFMS) is applied to qualitative and quantitative drug testing. Human serum was 'spiked' with known quantities of benzodiazepines and a 'street heroin' mixture including some of the major metabolites and impurities. The sample components were extracted from the matrix by solid-phase extraction (SPE). Constituents containing polar hydroxyl and/or secondary amine groups were derivatised with N-methyl-N-(tert-butyldimethyl)trifluoroacetamide (MTBSTFA) to improve the chromatographic performance. An orthogonal separation of the matrix constituents was achieved by coupling a DB-5ms (5% phenyl) to a BPX50 (50% phenyl) GC column. The eluant was focused onto the second column by a twin-stage cryo-modulator. Rapid 6 s modulation times were achieved by transfer from a 30 m x 0.25 mm (length x internal diameter) to a 2 m x 0.1 mm column. TOFMS with rapid spectral acquisition (< or =500 spectra/s) was employed in the mass range m/z 40-650. A clean mass spectrum was obtained for each analyte using mass spectral deconvolution software. The sensitivity and repeatability of the method were evaluated by the preparation of calibration standards for two benzodiazepines, flunitrazepam and its major metabolite 7-aminoflunitrazepam (7-amino-FN), in the concentration range 5-1000 ng/mL. The limits of detection (LODs) and limits of quantitation (LOQs), calculated by repeat injections (x10) of the lowest standard, were 1.6 and 5.4 ng/mL (flunitrazepam); 2.5 and 8.5 ng/mL (7-amino-FN), respectively. There is scope to extend this protocol to screen a large number of drugs and metabolites stored in a library database.

Forensic toxicological implication of an autopsy case of mixed drug overdose involving clomipramine, chlorpromazine and flunitrazepam

A case of fatal poisoning involving clomipramine, chlorpromazine and flunitrazepam is presented. Quantitative toxicological analysis showed that the concentrations of clomipramine, chlorpromazine and 7-aminoflunitrazepam (a metabolite of flunitrazepam) in the femoral blood were 3.24 microg/ml, 0.36 Kg/ml and 0.61 microg/ml, respectively, and large amounts of drugs were also detected from the stomach contents. We concluded that the cause of death was due to the combined use of clomipramine, chlorpromazine and flunitrazepam.

Field-Test of a Date-Rape Drug Detection Device

Drink Safe Technology Version 1.2 is an inexpensive color-change reagent test marketed internationally for use by consumers in settings such as a night club to detect potentially incapacitating concentrations of gamma-hydroxybutyric acid (GHB) and ketamine in beverages. The objective of this study was to compare product performance in the laboratory and performance in the hands of consumers in the field. Product performance in the laboratory adhered to the protocol defined by the manufacturer. Product performance in the hands of consumers in field settings allowed browsing participants to pipette an aliquot of their own drinks into randomly coded vials containing authentic drugs, or pure water, so as to yield the same concentrations of GHB or ketamine specified in the manufacturer-defined protocol, or blanks. Consumers were to proceed according to the directions printed on the product, and to record their results on a card with a code corresponding with the vial to which they had added an aliquot of their beverage. Diagnostic performance was calculated using two-way analysis. In the laboratory, Drink Safe Technology Version 1.2 reliably detected GHB and ketamine at concentrations specified by the manufacturer's protocol. The reactive color change denoting a positive test for GHB was rapid, but a positive test for ketamine required substantially more time to resolve. Nonetheless, test accuracy following the manufacturer's protocol in the laboratory was 100%. In the field, based on 101 paired-test results recorded by consumers, the test efficiency was 65.1%, sensitivity 50%, and specificity 91.6%. The product performed much better in the laboratory than it did in the hand of consumers in the field. There seems to be considerable potential for consumers to misinterpret a test result. The potential for consumers to record a false-negative test result for a spiked drink is cause for concern.

Characterization of two classes of benzodiazepine binding sites in Schistosoma mansoni

As we have recently shown that GABA should be considered a putative neurotransmitter inSchistosoma mansoni, the present work aimed to search for GABAAreceptors in adult worms using [3H]-flunitrazepam to label the allosteric benzodiazepine binding site which is classically present on GABAAreceptor complexes. We detected a large population (Bmax=8·25±1·1 pmol . mg protein−1) of high affinity (Kd=33·6±1·5 nm) binding sites for flunitrazepam. These sites harboured a singular pharmacological modulation that does not fit well with a mammalian central benzodiazepine receptor, mainly due to a very high affinity for Ro5-4864 and a very low affinity for clonazepam. We also detected a second population of benzodiazepine binding sites labelled with high affinity (IC50=85 nm) by [3H]-PK11195, a selective ligand of the mammalian peripheral benzodiazepine receptor. In conclusion, this work describes the pharmacological properties of a large population of central-like benzodiazepine receptors supporting their study as putative new targets for the development of anti-parasitic agents. We also describe, for the first time, the presence of peripheral benzodiazepine receptors in this parasite.

Possibilities and problems with identification and determination of "new" hypnotics

Authors discuss problems with identification and determination of flunitrazepam and zolpidem in biological material (BM). Over the recent years, these two structurally different substances have become the most frequently used as well as abused hypnotic drugs. This study presents applicability of immunochemical methods in the screening of flunitrazepam, one of the most commonly prescribed drugs among the benzodiazepines. Herein described techniques, a liquid-liquid (L-L) extraction, solid phase extraction (SPE) and the so-called "freeze out" method are used for isolation of the above mentioned compounds from BM. Besides the thin layer chromatography (TLC) and gas chromatography - mass spectrometry (GC-MS) applied in qualitative analysis, the study also describes a gas chromatography with electron capture detector (GC-ECD) and gas chromatography with nitrogen phosphorus detector (GC-NPD) optimized for the determination of flunitrazepam and zolpidem in blood (serum). Successful analyses of these two substances are of major importance, especially in interpreting the results of forensic toxicological examinations.

Sweeping technique combined with micellar electrokinetic chromatography for the simultaneous determination of flunitrazepam and its major metabolites

A sweeping technique, in conjunction with micellar electrokinetic chromatography, for the simultaneous determination of flunitrazepam and its major metabolites, 7-aminoflunitrazepam and N-desmethylflunitrazepam, is described. The optimized conditions for the sweeping and separation were a pH 9.5 buffer, 25mM borate, 50mM cetyltrimethylammonium bromide, 30% MeOH (v/v), and a 151-mm injection length. The calibration functions were all linear with the coefficient of determination (r(2)) exceeding 0.996 for the three target compounds. Using the sweeping procedure, the limits of detection were determined to be 13.4, 5.6, and 12.0ng/mL for flunitrazepam, 7-aminoflunitrazepam, and N-desmethylflunitrazepam, respectively, and the sensitivity enhancement for each compound was within the range of 110-200 fold. The RSDs for the retention time and the peak area were less than 4.10%. The optimized sweeping method was also used to examine a spiked urine sample. We conclude that sweeping with micellar electrokinetic chromatography has considerable potential use in clinical and forensic analyses of flunitrazepam and its metabolites.

Screening for drugs of abuse in hair with ion spray LC–MS–MS

Analyzing hair for many substances can be tedious and expensive, and a rapid screening method should prove helpful. Generally, screening has been performed using immunological tests, mainly in workplace drug testing, where the number of samples has been high. The aim of this study was to develop an LC-MS-MS method for the simultaneous analysis of several drugs of abuse in human hair as an alternative to immunological screening tests. In 75 randomly selected autopsy cases, hair was analyzed in addition to the usual specimens of blood and urine. The method included nicotine, cotinine, morphine, codeine, 6-acetylmorphine, ethylmorphine, amphetamine, methamphetamine, MDA, MDMA, benzoylecgonine, cocaine, 7-aminoflunitrazepam and diazepam. The LC-MS-MS analysis was performed on a SCIEX API 2000 MS-MS instrument equipped with an electrospray interface. To 20-50 mg of hair, 0.5 ml of mobile phase A (acetonitril:methanol:20 mM formate buffer, pH 3.0 (10:10:80)) and 25 microl of internal standard were added and the sample was incubated in a water bath at 37 degrees C during 18 h. Using a threshold of 20 ng/sample, equivalent to 1 ng/mg if 20mg hair is used, 26 positive results were found in 16 cases. Three of the 26 positive detections could not be confirmed by GC-MS. Two of the cases were not previously known as drug users. Of the 59 negative cases, only one case had a positive blood sample showing 0.01 and 0.07 microg/g femoral blood of 6-acetylmorphine and morphine, respectively. This might indicate drug abstinence resulting in decreased tolerance or even a "first time" use of heroin resulting in death. We conclude that the use of hair analysis in postmortem cases can reveal both unknown drug use, as well as confirm a period of drug abstinence prior to an acute fatal overdose. The proposed LC-MS-MS method showed high sensitivity, was very easy to perform and seemed appropriate for screening purposes.

Quantitative determination of diazepam, nitrazepam and flunitrazepam in tablets using thin-layer chromatography-densitometry technique

A simple and reliable assay for diazepam, nitrazepam and flunitrazepam in tablets by high-performance liquid chromatography (HPLC) and thin-layer chromatography (TLC)-densitometry is described. A quantity of a ground tablet mass, equal to the average weight of one tablet was sonicated in MeOH, mixed with appropriate internal standard, filtered and either injected directly into the liquid chromatograph, or after evaporation and reconstitution of an aliquot of the extract, was spotted on a silica gel thin-layer plate. A variable UV detector, operated at 254 nm was employed in both procedures. A C18, reversed phase 7 microm column was used for HPLC analysis; the mobile phase was a 1:1 (v/v) mixture of MeOH (40 degrees C) and 0.01 M phosphate buffer (pH 7, 80 degrees C). The TLC plate was developed in an unsaturated chromatographic chamber containing 100 ml chloroform-acetone (9:1); at room temperature, the mobile phase was allowed to travel 15 cm. The percentage of the active ingredient content of each tablet obtained by both procedures, was in the range of the stated amount except for one brand of diazepam tablets which contained approximately 23% less active ingredient than the minimum prescribed amount. The TLC densitometry, although yields slightly higher values than the HPLC method, is preferred due to its simplicity, ease and low cost.

The GABA(A) receptor complex in the chicken brain: immunocytochemical distribution of alpha 1- and gamma 2-subunits and autoradiographic distribution of BZ1 and BZ2 binding sites

Two antibodies, raised against the rat GABA(A) receptor alpha1- and gamma2-subunits, were used for an immunocytochemical study of the distribution of these proteins in the chicken brain. The immunoreactive bands obtained by Western blotting and the similar labelling distribution found in the rat and chicken brain support the suitability of these antibodies for the labelling of GABA(A) receptors in birds. We found abundant alpha1 and gamma2 immunoreactivity throughout the chicken brain, mainly in the paleostriata and lobus paraolfactorius, dorsal thalamus and some nuclei of the brainstem. The alpha1-subunit was more abundant in the telencephalon, thalamus and cerebellum, while the presence of the gamma2-subunit was stronger in the optic tectum and brainstem. We also report the autoradiographic distribution of the BZ1 and BZ2 benzodiazepine receptor subtypes in the chicken brain using [3H]flunitrazepam. Benzodiazepine binding was unevenly distributed throughout the chicken brain, and the anatomical distribution of the BZ1 and BZ2 subtypes was similar to that described in mammals. The highest binding values were found in the olfactory bulb, paleostriatum primitivum, optic tectum, nucleus mesencephalicus lateralis pars dorsalis and nucleus isthmi pars parvocellularis, the BZ2 subtype being predominant in the paleostriatum primitivum and optic tectum. A general agreement in the distribution of BZ1 and alpha1 immunoreactivity was observed in structures such as the olfactory bulb, paleostriata, lobus parolfactorius and dorsal thalamus, although some discrepancies were observed in areas such as the optic tectum or nucleus isthmi pars parvocellularis, with high BZ1 binding and low or no alpha1 immunolabelling.

Microemulsion electrokinetic chromatography versus capillary electrochromatography-UV-mass spectrometry for the analysis of flunitrazepam and its major metabolites

Benzodiazepines, namely flunitrazepam and its three major metabolites, were successfully separated by microemulsion electrokinetic chromatography. Separation was achieved using an untreated fused-silica capillary (48 cm (effective length 40 cm) x 50 num) at 25 kV; detection was performed by UV at 220 nm. The microemulsion system consisted of 70 mM octane, 800 mM 1-butanol, 80 mM sodium dodecyl sulfate (SDS) and 10 mM borate buffer, pH 9. Very high efficiencies (up to 400 000 plates) and resolution better than 3 were achieved. Since this technique is not compatible with mass spectrometry (MS) detection, a capillary electrochromatographic (CEC) method was developed to separate flunitrazepam and its metabolites. The effects of mobile phase composition and pH as well as voltage and temperature were systematically investigated. The optimized CEC method allowed the baseline separation of the investigated compounds. For the on-line coupling of CEC with electrospray ionization-mass spectrometry, the column was connected to a void fused-silica capillary using a Teflon connection. This configuration was found efficient and suitable for hyphenation of commercial CEC and MS instrumentation using commercially available CEC columns.

Detection of flunitrazepam and 7-aminoflunitrazepam in oral fluid after controlled administration of rohypnol

Although administered as a short-acting hypnotic for sleeping disorders, flunitrazepam, often in combination with alcohol or other drugs, was one of the most frequently abused benzodiazepines over the last 10 years. It has been reported in cases of driving under the influence, and its use is associated with marked psychomotor impairment. Studies over the last five years have investigated the use of oral fluid as an alternative matrix to blood and urine, especially when non-intrusive and quick sampling procedures are important (e.g., screening for drugs of abuse at the roadside and screening and confirmatory workplace drug testing). In this study, Rohypnol (flunitrazepam) was administered to four healthy volunteers, and oral fluid samples were collected by spitting into a polypropylene tube at fixed times between 0 and 6 h after the intake of a tablet of 1 mg. A specific and very sensitive method was developed, both for flunitrazepam and for its main metabolite 7-aminoflunitrazepam, based on solid-phase extraction of the oral fluid samples, stored at +4 degrees C, and gas chromatographic-mass spectrometric analyses using negative chemical ionization with methane as the ionization gas. The heptadeuterated parent compound and metabolite were used as internal standards. The respective limits of detection and quantitation were 0.05 microg/L and 0.1 microg/L for flunitrazepam, and 0.1 and 0.15 microg/L for 7-aminoflunitrazepam. The parent drug could only be detected when the analyses were performed within 12-24 h after collection of the oral fluid samples or when 2% of NaF was added to the collection tubes. The stability of flunitrazepam in oral fluid was poor, even at +4 degrees C, when no NaF was added to the sample. In any case, concentrations remained below 1 microg/L. The metabolite was detected in slightly higher concentrations, with or without the presence of NaF, reaching a maximum of 1-3 microg/L within 2-4 h after administration. In all cases the drug was detectable, but at extremely low concentrations, for 6 h after intake of a normal dose of Rohypnol and it will be an analytical challenge to come up with a sufficiently sensitive onsite test for low-dose benzodiazepines in oral fluid.

Determination of benzodiazepines in human hair by on-line high-performance liquid chromatography using a restricted access extraction column

A method is described for the identification of five frequently prescribed benzodiazepines (BZD) (clonazepam, diazepam, flunitrazepam, midazolam and oxazepam) in human hair samples by reversed phase HPLC, following on-line simple enrichment and clean-up on a restricted access extraction column. 50mg of powdered hair were incubated (2h at 45 degrees C) after sonication (1h) in 1 ml of the following solution (methanol:ammonia, 97.5/2.5, v/v). The aliquot was centrifuged and the methanolic phase transferred to a conical tube and evaporated under a gentle stream of nitrogen. The residue was reconstituted by adding 100 microl of a mixture of phosphate buffer (20mM, pH=2.2) and acetonitrile (94/6, v/v). A total of 80 microl were injected into the system with the column switching technique. The pre-column or clean-up column was washed with phosphate buffer pH=7.2. The drugs retained on the pre-column were then eluted in the back-flush mode and separated on a C(8) semi micro column, Lichrospher select B, 125 mm x 3 mm. The BZD were determined by a photodiode-array detector at 254 nm, using reference data (retention time and UV spectra) stored in a personal library. The method showed excellent linearity between 0.5 and 20 ng/mg of hair for clonazepam, flunitrazepam and midazolam and between 0.5 and 100 ng/mg of hair for diazepam and oxazepam. Finally, the present method has been applied to a number of forensic cases in our laboratory.

Deposition of 7-aminoflunitrazepam and flunitrazepam in hair after a single dose of Rohypnol

In recent years, there has been a notable increase in the number of reports on drug-facilitated sexual assault. Benzodiazepines are the most common so-called "date-rape" drugs, with flunitrazepam (Rohypnol) being one of the most frequently mentioned. The aim of this study was to determine whether flunitrazepam and its major metabolite 7-aminoflunitrazepam could be detected in hair collected from ten healthy volunteers after receiving a single 2 mg dose of Rohypnol using solid phase extraction and NCI-GC-MS. Such data would be of great importance to law enforcement agencies trying to determine the best time interval for hair collection from a victim of drug-facilitated sexual assault in order to reveal drug use. Ten healthy volunteers (eight women and two men, 21 to 49 years old) participated in the study. The following hair samples were collected from each volunteer: one before flunitrazepam administration, and 1, 3, 5, 14, 21, and 28 days after. In five volunteers, 7-aminoflunitrazepam was detected 24 h after flunitrazepam administration and remained in hair throughout the entire 28-day study period (0.6-8.0 pg/mg). In two cases, 7-aminoflunitrazepam appeared in hair 21 days after drug intake (0.5-2.7 pg/mg), and in two subjects 14 days later (0.5-5.4 pg/mg). In one volunteer, 7-aminoflunitrazepam was detected on day 14 and 21 but concentrations were below the quantitation limit. Flunitrazepam was detected in some samples but all concentrations were below the quantitation limit (0.5-2.3 pg/mg).

High-performance liquid chromatography determination of flunitrazepam and its metabolites in plasma by use of column-switching technique: comparison of two extraction columns

A study, using on-line column-switching high-performance liquid chromatography, evaluated two different extraction columns for the determination of flunitrazepam and its major metabolites: 7-aminoflunitrazepam, 7-acetamidoflunitrazepam and desmethylflunitrazepam. The procedure was based on the enrichment of benzodiazepines on the extraction column, followed by transfer of the compounds to the analytical column. The two extraction columns were compared: the first column was a BioTrap 500 MS (hydrophobic polymer), 20x4 mm I.D., and the second was a LiChrospher RP-18 ADS, 25x4 mm I.D. The analytical column used was a LiChrospher select B RP-8, 125x3 mm I.D. with 5 microm particle size. The extraction conditions for the two pre-concentration columns, such as extraction temperature, buffer concentration, buffer pH, acetonitrile percentage and flow-rate, were studied for the extraction from plasma of flunitrazepam and its metabolites mentioned above. The mobile phase of the analytical column was isocratic and composed of acetonitrile-20 mM phosphate buffer at pH 2.1 (35:65, v/v) and at a flow-rate of 0.3 ml/min.

Fatal acute alcohol intoxication in an ALDH2 heterozygote: a case report

On an evening in November, a 25-year-old man was found dead in his bedroom. There were many empty snap-out sheets for flunitrazepam tablets in the trash at his bedside. He had been beaten by a gang of young people earlier in the morning of the same day. At the medico-legal autopsy, although there were many bruises and/or abrasions on the whole body, only slight subdural hemorrhage was observed, and none of them was thought to be the cause of death. Flunitrazepam and its metabolites were not detected in his body fluid by gas chromatography-mass spectrometry (GC-MS). Marked lung edema and a severe congestion of organs were observed. His blood alcohol concentration from the femoral vein was 2.00 mg/ml. Fatal cases of acute alcohol intoxication usually have shown higher alcohol concentration (2.25-6.23 mg/ml). Although the genotype of aldehyde dehydrogenase 2 (ALDH2) has not previously been mentioned as a contributing factor in determining the cause of death, in this case the genotype of ALDH2 was ALDH2*1/2 and thus is important. Those who possess the ALDH2*2 gene show high concentrations of acetaldehyde (AcH) at even comparatively lower alcohol levels. Consequently, the cause of death was considered to be acute alcohol intoxication including AcH poisoning.

A comparison of sodium hydroxide and sodium sulfide digestion of mouse hair in the recovery of radioactivity following systemic administration of [3H]-nicotine and [3H]-flunitrazepam

Pigmented (C57BI) and nonpigmented (balb/c) mice, 25 days of age, were treated intraperitoneally with [3H]-nicotine (4 mg/kg, 555 dpm/ng) or [3H]-flunitrazepam (1 mg/kg, 2200 dpm/ng) daily for three days. After 21 days, shaved back hair was digested at 37 degrees C for 24 h with either 1 M sodium hydroxide or 1 M sodium sulfide. With both drugs, sodium sulfide extraction removed the same amount of radioactivity as sodium hydroxide from nonpigmented hair. However, sodium sulfide removed significantly more radioactivity from pigmented hair than did sodium hydroxide. In pigmented hair, sodium sulfide solubilized 35% and 74% of the flunitrazepam- and nicotine-associated radioactivity, respectively. Of this, 12% and 43%, respectively, could be partitioned into ethyl acetate. Microscopic examination of residual pellets after digestion demonstrated a more thorough dissolution of the hair shaft with sodium sulfide with only melanosomes remaining. The results demonstrate the significant interaction of flunitrazepam and nicotine with melanins and the utility of sodium sulfide in increasing drug recovery.

Highly sensitive micro-plate enzyme immunoassay screening and NCI-GC-MS confirmation of flunitrazepam and its major metabolite 7-aminoflunitrazepam in hair

Flunitrazepam (Rohypnol) is a benzodiazepine used in the treatment of insomnia as a sedative hypnotic and as preanesthetic medication in European countries and Mexico. Although it has no medicinal purpose in the United States, the occurrence of its abuse is increasing. Sexual abuse of both men and women while under the influence of so-called "date-rape" drugs has been the focus of many investigations. Reported date-rape drugs include flunitrazepam (FN), clonazepam, diazepam, oxazepam, gamma-hydroxybutyrate, and many others. FN has been banned in the United States because of its alleged use in such situations. Unfortunately, the detection of FN or its metabolites 7-aminoflunitrazepam (7-AFN) and desmethylflunitrazepam in a single specimen such as urine or blood is difficult in criminal situations because of the likelihood of single-dose ingestion and the length of time since the alleged incident. Hair provides a solution to the second of these problems in that drugs tend to incorporate into hair and remain there for longer periods of time than either urine or blood. There are various techniques for the detection of FN in plasma, blood, and urine, but little work has been done with hair. Hair collection is a virtually noninvasive procedure that can supply information on drug use for several months preceding collection. The objective of this paper was to determine if a commercially available micro-plate enzyme immunoassay system was sufficiently sensitive for the routine screening of 7-AFN in hair by the development of extraction procedures and optimization of the immunoassay kit. Further, this study used the same solid-phase extraction to isolate FN and its major metabolite, 7-AFN, and gas chromatography-mass spectrometry with negative ion chemical ionization for confirmation. Two seven-point standard curves were established ranging from 0.5 pg/mg to 100 pg/mg for 7-AFN and 2.5 pg/mg to 200 pg/mg for FN with respective deuterated internal standards. A replicate analysis of controls was performed to establish inter- and intraday variabilities. Two suicide cases along with one alleged date-rape case and one case of an emergency room patient whose blood screened positive for benzodiazepines were analyzed. All the hair specimens screened positive for benzodiazepines using micro-plate enzyme immunoassay. Two cases, including the date-rape case, were negative for FN and 7-AFN, and two postmortem hair samples were confirmed positive for FN and its metabolite.

Simple and rapid color screening tests for flunitrazepam (Rohypnol)

Three new color/screening tests for flunitrazepam (Rohypnol) are reported. The two-step tests are simple, sensitive, highly specific, and effective for both cut and uncut flunitrazepam and standard over-the-counter preparations of flunitrazepam (i.e., Rohypnol tablets).

Determination of benzodiazepines in human urine and plasma with solvent modified solid phase micro extraction and gas chromatography; rationalisation of method development using experimental design strategies

Solid phase micro extraction (SPME) and gas chromatographic analysis was used for the analysis of several benzodiazepines (oxazepam, diazepam, nordiazepam, flunitrazepam and alprazolam) in human urine and plasma. Several factors likely to affect the analyte recovery were screened in a fractional factorial design in order to examine their effect on the extraction recovery. Parameters found significant in the screening were further investigated with the use of response surface methodology. The final conditions for extraction of benzodiazepines were as follows: Octanol was immobilised on a polyacrylate fibre for 4 min. The fibre was placed in the sample and extraction took place at pH 6.0 for 15 min. Urine samples were added to 0.3 g ml(-1) sodium chloride. In plasma, the extraction recovery was less than in urine and releasing the benzodiazepines from plasma proteins followed by protein precipitation was found necessary prior to sampling. The method was validated and found linear over the range of samples. The limits of detection in urine were determined to be in the range 0.01-0.45 micromol l(-1). The corresponding limits of detection in plasma were in the range 0.01-0.48 micromol l(-1). Finally, the method developed was applied to determine some benzodiazepines after administration of a single dose. This method offers sufficient enrichment for bioanalysis after a single dose of high dose benzodiazepines as diazepam, but for low dose benzodiazepines as flunitrazepam, further sensitivity is needed.

Recreational drugs. Current trends in the 90s

Recreational drug use continues to be prevalent in many social settings. These drugs are alleged to enhance sociability and liberate inhibitions, allowing the user to experience feelings of euphoria. This article reviews recreational drugs that have gained notoriety in the 1990s including gamma-hydroxybutyrate (GHB), flunitrazepam, and amphetamine analogues such as 3,4-methylenedioxyamphetamine (MDA), 3,4-methylenedioxymethamphetamine (MDMA), and 3,4-methylenedioxyethylamphetamine (MDEA). Topics discussed include history, drug use and misuse, clinical presentation and treatment, and laboratory analysis.

Postmortem distribution and redistribution of nitrobenzodiazepines in man

The distribution of the nitrobenzodiazepines, flunitrazepam, clonazepam and nitrazepam, and their respective 7-amino metabolites were examined in blood, serum, vitreous humor, liver, bile and urine of decedents taking these drugs. Peripheral blood, serum and liver concentrations were not significantly different to each other. However, vitreous concentrations were one-third of blood, while bile concentrations were 5-12 fold higher. Blood, serum and vitreous contained predominantly the 7-amino metabolite, liver contained only the metabolite, while bile contained significant concentrations of both the parent drug and the 7-amino metabolite. Urine contained only small concentrations of parent drug, however, as expected a number of metabolites were detected. Redistribution studies compared the drug concentrations of femoral blood, taken at body admission to the mortuary, with femoral blood taken at autopsy approximately 39 h later in 48 cases. The concentrations of 7-amino metabolites were not significantly different, however the concentrations of parent nitrobenzodiazepines were significantly higher in the admission specimens. In 6 cases in which subclavian blood was taken, the concentrations were not significantly different to the concentrations in admission blood. Similar findings were observed when femoral and subclavian blood concentrations were compared in 6 cases. There was also no apparent difference in total blood concentrations of nitrobenzodiazepines when blood concentrations taken in hospital shortly prior to death were compared to postmortem blood. Postmortem diffusion into peripheral blood is therefore not a confounding factor in the interpretation of nitrobenzodiazepine concentrations.

Localization of flunitrazepam in artificial membranes. A spectrophotometric study about the effect the polarity of the medium exerts on flunitrazepam acid-base equilibrium

In the present paper we tried to test the hypothesis that nonspecific flunitrazepam-membrane interactions are consistent with drug molecules accommodated between lipid molecules, becoming an integral part of the bilayer. We developed a spectrophotometric method to determine FNTZH+ equilibrium dissociation constant and applied it to the study of the acid-base equilibria of this drug in homogeneous media of different polarity. In these conditions, pK decreased with the decrement in the dielectric constant (D) of the media. These results, analyzed under the light of the theory developed by Fernandez and Fromherz (1977; J. Phys. Chem. 81, 1755-1761) let us infer that flunitrazepam is localized a region with D = 60. This D value is lower that Dwater = 78 and higher than D of hydrocarbon chains zone (D = 2-5) and would correspond to D of the region of polar groups. This result is compatible with the hypothesis.

Detection of benzodiazepines and other psychotropic drugs in human hair by GC/MS

For the detection of psychotropic drugs in human hair we collected hair obtained from 21 corpses that died from an overdose of legal or illicit drugs. These persons were known to have taken psychotropic drugs prior to their death as determined by post-mortem toxicological analysis in blood. After washing, cutting hair into segments of 3 cm, pulverization, enzymatic hydrolysis with beta-glucuronidase/arylsulfatase and solid phase extraction, drugs were identified by GC/MS. For quantification of flunitrazepam we used its metabolite amino-flunitrazepam; for oxazepam and lorazepam we used the hydrolysed forms of the corresponding drugs. In the hair of 21 subjects tested we found in 20 cases nordazepam, in 15 cases diazepam, in 15 cases oxazepam and in eight cases flunitrazepam with maximal concentrations of 1.8, 2.2, 3.4 and 9.5 ng/mg hair respectively. In addition to these compounds, in subject 11 to 21 we also analyzed for and detected amitriptyline (seven positive), carbamazepine (eight positive), lormetazepam (three positive) and lorazepam (one positive) and found maximal concentrations of 106.0, 13.5, 29.0 and 4.9 ng/mg hair respectively. The comparison of hair analysis versus post-mortem blood and tissues analysis of all the drugs studied shows that in 40 cases, where a positive result was found in blood, the corresponding drug could also be detected in hair in 37 cases. Our results show that hair testing is complementary to classical post-mortem analysis in forensic toxicology.

Testing human hair for flunitrazepam and 7-amino-flunitrazepam by GC/MS-NCI

To validate information on flunitrazepam use, we investigated human hair for flunitrazepam and its major metabolite 7-amino-flunitrazepam by gas chromatography coupled to mass spectrometry in negative chemical ionization mode of detection. Samples were twice decontaminated with methylene chloride, pulverized in a ball mill and 50 mg of powdered hair were incubated in Soerensen buffer (pH 7.6) in the presence of diazepam-d5 used as internal standard. After liquid-liquid extraction of the incubation medium with diethylether-chloroform (80:20, by vol.), the organic phase was evaporated and the dry extract was derivatizated with heptafluorobutyric anhydride. Benzodiazepines were separated on a 30 m capillary column and detected using single ion monitoring. Among 40 hair samples tested (obtained from drug addicts deceased by heroin overdose), 14 were positive for both flunitrazepam and 7-amino-flunitrazepam and 12 for 7-amino-flunitrazepam only. Concentrations ranged from 31 to 129 pg/mg (mean: 60 pg/mg) and from 3 to 161 pg/mg (mean: 46 pg/mg) for flunitrazepam (14 cases) and 7-amino-flunitrazepam (26 cases), respectively. This first report described the detection of flunitrazepam and 7-amino-flunitrazepam in hair of chronic abusers. Due to the low concentrations observed, negative chemical ionization appears to be the alternative to test flunitrazepam and other benzodiazepines in hair.

Determination of chronic flunitrazepam abuse by hair analysis using GC-MS-NCI

A 38-year-old male was found comatose at home with an empty package of Rohypnol (2-mg tablets, 10 per package) near the body. Many other drugs, which had recently been stolen from a pharmacy, were also found. The judge in charge of the investigation of the stolen pharmaceuticals asked our laboratory to determine if the subject was a chronic user of flunitrazepam, leading our laboratory to develop a procedure for the detection of this benzodiazepine in human hair. The method involved decontamination of hair samples with dichloromethane, incubation in Sorenson buffer (pH 7.6) in the presence of diazepam-d5 used as internal standard, direct liquid-liquid extraction with diethylether-chloroform (80:20, v/v), derivatization with heptafluorobutyric anhydride and analysis by gas chromatography coupled to mass spectrometry in the negative chemical ionization mode of detection. Flunitrazepam and its major metabolite, 7-amino-flunitrazepam, were both detected. The concentrations determined in the proximal hair segment were 89.5 and 24.0 pg/mg for flunitrazepam and 7-amino-flunitrazepam, respectively.

An autopsy case of abandoned infant body with severe destruction

One case of infanticide and abandonment by the natural mother is presented. The body was extensively damaged, evidently by a fox. Fortunately, since the body showed less advanced putrefaction due to cold weather, it was possible to narrow down the cause of death and to detect the drug which had been forced down the victim's throat before the crime. However, our estimates of age and postmortem interval were erroneous. We comment as to why we were misled. Pathological problems associated with "aspiration of vomitus" are also discussed.

[Determination of benzodiazepines by thermospray liquid chromatograph-mass spectrometer. Part 1. Nitrazepam, estazolam, bromazepam, flunitrazepam]

Thermospray liquid chromatography mass spectrometric method is described for the determination of the benzodiazepines (Nitrazepam, Estazolam, Bromazepam, Flunitrazepam). Reversed-phase liquid chromatography was performed using a 15 cm Shim-pack CLC-ODS (Shimadzu) column, with acetonitrile-water (40:60) + 0.1 M ammonium acetate as mobile phase, at a flow rate of 1.0 ml/min. The temperature of the vaporizer, block and TH of the source block were 166, 270 and 275 degrees C, respectively. Positive ion thermospray mass spectra by thermospray ionization (TSP ionization) mode or thermospray on filament ionization (filament-on ionization) mode were obtained. Formation of the MH+ ion was observed as a base peak under TSP ionization and filament-on ionization conditions and fragment ions were very few. On both ionization mode, peaks representing nitrazepam as MH+ at m/z 282 at a retention time (R.T.) of 6.4 min, from estazolam as MH+ at m/z 295 at an R.T. of 6.4 min, from bromazepam as MH+ at m/z 316 at an R.T. of 4.5 min and from flunitrazepam as MH+ at m/z 314 at an R.T. of 8.8 min. The detection limit for all the benzodiazepines under investigation was less than 0.5 ng (S/N = 9.4 +/- 4.6) using selected ion monitoring.

Subcellular localization of two neurotropic drugs in three varieties of central nervous system cells by secondary ion mass spectroscopy (SIMS) microscopy

The intracellular localization of two neurotropic drugs, flunitrazepam (benzodiazepine) and triflupromazine (phenothiazine), was studied by secondary ion mass spectrometry microscopy (SIMS) in three varieties of cells. The images of the intracellular distributions of the two drugs are easily obtained by selecting the fluorine atom of the molecules. These images show that the drug from the benzodiazepine group is mainly located in the nuclei, whereas the phenothiazine is exclusively located inside the cytoplasm.

Hydrolysis of clonazepam, flunitrazepam and nitrazepam by hydrochloric acid. Identification of some additional products

Several by-products in the hydrochloric acid hydrolysis of clonazepam, flunitrazepam and nitrazepam are isolated by a combination of TLC and HPLC. With mass and NMR spectroscopic methods the structures of the by-products are established. Some indications are given for possible modes of formation of the by-products.

Application of I.R. spectrophotometry in emergency analyses

I.R. spectrophotometry has been applied in emergency toxicological analyses. Poisons and drugs are extracted into chloroform, potassium bromide is added to the extract and the solvent evaporated. Potassium bromide discs are prepared by compression and scanned in an I.R. spectrophotometer. A data bank of standard spectra has been prepared and computerized comparison of the spectral data of the sample extract with those of authentic compounds allows the identification of toxic agents in 'real time'.

[Analytical data of flunitrazepam (rohypnol), a new benzodiazepine-derivative, in special consideration of its metabolites (author's transl)]

The article describes analytical data (TLC, GLC, IR, UV and MS) of flunitrazepam, 7-amino-flunitrazepam, desmethylflunitrazepam, 3-hydroxyflunitrazepam, 7-amino-desmethyl-flunitrazepam and many other benzodiazepine-derivatives, especially aminobenzophenones. Also extraction from biological specimen is reported.