Reagent drug detection

Stohs and Scratchley (53) investigated several thin layer chromatography systems for thiazide diuretics and antihypertensive drugs, using silica gel G and a variety of detection reagents. 

Detection reagents may be selected for specificity based on other drugs or metabolites expected in the sample. A sensitivity of 1-10 meg. is normally obtainable. The following means of visualization have been used 0.5-1% silver nitrate or acetate-white58 ... 

Use Intermediate for dyes and drugs, sensitive reagent for detection of cyanide. 

Cons This format can result in false-positive results if there are other factors in the serum beside anti-drug antibody that may form a bridge between the capture and detection reagents. The bridging assay is affected more by free drug interference than the sandwich or indirect assays. 

Ng (1991) has provided a review on TLC and HPTLC analysis of the more popular pharmaceuticals and illicit drugs covering the literature from about 1975 to 1988. This reference includes information on sample preparation, layers, mobile phases, detection reagents, and structures of popular human and animal drugs. Numerous examples are provided for qualitative and quantitative TLC analysis of pharmaceutical drugs in various dosage forms. The review of Ng (1991) was extended and updated by Szepesi and Nyiredy (1996) to include references through 1995. 

Touchstone (1992) has provided information on methods of sample preparation, layers, mobile phases, and detection reagents for pharmaceuticals, particularly drugs of abuse such as amphetamines, barbiturates, benzodiazepines, canna-binoids, cocaine, methaqualone, opiates, and anorexicants. 

Many alkaloids are derivatives of tertiary amines and, as the name implies, are alkaline in nature. Numerous drugs of abuse as well as abused drugs are alkaloids. An extensive list of alkaloids, their sample preparation, solvent systems, and detection reagents have been given by Wagner et al. (1984). 

Other solvent systems and detection reagents are recommended for the identification and confirmation of drugs and their metabolites. These include ethyl acetate-methanol-concentrated ammonium hydroxide (90 7 3) with detection by fluorescamine, diphenylcarbazone, and iodoplatinate reagents for D-amphet-amine, barbiturates, and acidic drugs (e.g., phenobarbital, Dilantin, Mellaril, Valium, chlorpromazine, Lomotil, and Talwin) and ethyl acetate-methanol-concentrated ammonium hydroxide-water (85 13.5 0.5 1.0) with detection by... 

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