Improved cost effective thin-layer detection techniques for routine surveillance of commonly abused drugs in drug abuse urine screening and proficiency testing programs with built-in quality assurance.

Improved, sensitive, reliable and cost effective thin-layer detection procedures for poly-drug usage (12-15 drug evaluations per specimen) are presented. Extraction procedures using ion-exchange resin loaded paper and liquid-liquid extraction with the built-in quality assurance program are reported. The combined use of ninhydrin-fluorescamine detection reagent for the identification of various central nervous system stimulants is only one of the several modifications and improvements made during the past 14 years. Laboratories, participating in proficiency testing programs in drug abuse toxicology monitoring are encourage the use of proposed extraction and identification techniques.

Qualitative detection of placidyl (ethchlorvynol) alone or in combination with poly-drugs in drug abuse urine screening programs using ion-exchange paper and/or liquid-liquid extraction.

Two procedures for the detection of ethchlorvynol are presented. Procedure I involves the use of SA-2-cation-exchange resin loaded paper. The use of multiple ion-exchange resin papers is proposed in a sequence that enables the detection of amphetamines, barbiturates, phenothiazines, propoxyphene (Darvon), phencyclidine, cocaine (benzoyl ecgonine), pentazocine (Talwin) and benzodiazepines in addition to ethchlorvynol. This procedure discusses the details of detecting ethchlorvynol in combination with the entire array of drugs of abuse depending on the needs of a clinical program. Procedure II involves the principle of liquid-liquid extraction using either raw or spent urines.

Thin-layer detection of diazepam and/or chilordiazepoxide alone or in combination with major drugs of abuse in drug abuse urine screening programs.

Three extraction procedures for the detection of diazepam, oxazepam, chlorazepate and/or chlordiazepoxide in human urines are presented. All three procedures are based on the acid hydrolysis of benzodiazepines and/or their conjugated metabolites to give the corresponding benzophenones. Procedure I involves the direct acid hydrolysis of raw urine and is recommended when the aim is to test the abuse of benzodiazepine derivatives only. Procedure II Is a two-step extraction method in which a wide variety of drugs of abuse including cocaine (test based on the detection of benzoylecgonine) are extracted by the first step using paper loaded with cation-exchange resin and the benzodiazepines are tested in the second step by the acid hydrolysis of the spent urine left after removing the ion-exchange paper. Procedure III involves the use of inert fibrous matrix and then its acid hydrolysis. The detection procedure is based on the identification of methylaminochlorobenzophenone (MACB) and aminochlorobenzophenone (ACB). MACB is detected as a yellow-colored compound while ACB is detected by spraying with Bratton-Marshall reagent. Specificity of detection of ACB has been achieved by the selection of a thin-layer developing solvent system in which sulfonamides with primary aromatic amino groups remain at the origin.

Single- and two-step extraction and thin-layer detection procedures for benzoylecgonine (cocaine metabolite) alone or in combination with a wide variety of commonly abused drugs in urine screening programs.

Three extraction procedures for the detection of benzoylecgonine (a major metabolite of cocaine) in urine are presented. Each technique has its advantages, depending on the needs of a clinical operation. Procedures I and II involve the use of ion-exchange resin-loaded paper. Procedure I has a sensitivity of 1 microng/ml and requires 20 ml of urine, and is recommended when the aim is to test for the abuse of cocaine only. Procedure II is a two-step extraction method in which a wide variety of abused drugs are extracted by the first step and the benzoylecgonine left in the aqueous buffer phase is extracted in the second step. The sensitivity for benzoylecgonine using this procedure is 2 microng/ml and it requires 20-50 ml of urine. Procedure III involves the direct extraction of benzoylecgonine using 5 ml of urine and has a sensitivity of 0.5 microng/ml.

Comparison of costs for testing a wide variety of drugs of abuse per urine specimen in a drug abuse urine screening program and frequent urine collections.

Existing urine testing techniques in a drug abuse urine screening program with their capacity to analyze urine specimens per day are discussed. The start-up cost using each technique and cost per specimen are presented. A single step extraction technique using ion-exchange paper to absorb drugs prior to thin-layer chromatography (TLC) as reported by these laboratories will cost $0.58 per specimen, for testing the entire aray of drugs of abuse (at least 9-14 tests per specimen). Sensitivity reported using TLC technique for the morphine base is 0.15 mug/ml (minimum volume of urine needed 20 ml), 0.10 mug/ml if the volume of urine available is 30-35 ml, and 0.07 mug/ml if the volume of urine available is 43-50 ml.

Simultaneous detection of a wide variety of commonly abused drugs in a urine screening program using thin-layer identification techniques.

A single-step extraction method and thin-layer identification techniques capable of testing a wide variety of drugs of abuse are presented. These techniques are well suited for large and/or small drug programs involved in urine testing because they provide substantial economic benefits and improve clinical functioning. The drugs are absorbed on a 6 X 6 cm piece of paper loaded with cation-exchange resin and then eluted from the paper at pH 10.1 using ammonium chloride-ammonia buffer. The simultaneous thin-layer detection of sedatives, hypnotics, narcotic analgesics, central nervous system stimulants and miscellaneous drugs is accomplished by spotting the solution of extracted residue on a 20 X 20 cm Gelman pre-coated silica gel glass microfiber sheet (ITLC Type SA). A two-stage solvent system is used in order to obtain a chromatogram with optimum separation of a wide range of drugs. This system can separate methadone and/or cocaine from propoxyphene, methaqualone, methylphenidate, pentazocine, pipradrol, Doxepin, chlorpromazine, phenazocine, naloxone, naltrexone, imipramine and trimeprazine; amphetamine from phenylpropanolamine and dimethyltryptamine; codeine from dextromethorphan; methamphetamine from dimethyltryptamine, etc. Different detection reagents are then applied in succession to different marked areas of the developed chromatogram. This elegant method of extraction and spraying has enabled us to detect morphine base at a sensitivity level of 0.15 mug/ml, amphetamine sulfate at 1.0 mug/ml, methamphetamine hydrochloride at 0.5 mug/ml, phenmetrazine hydrochloride at 0.5 mug/ml, codeine phosphate at 0.5 mug/ml, methadone hydrochloride at 1.0 mug/ml, secobarbital at 0.36 mug/ml and phenobarbital at 0.5 mug/ml in urine. The minimum volume of urine needed to achieve these sensitivities is 20 ml. The cost of analysis per urine specimen using these techniques for concomitant screening of these drugs is less than US$ 1.