Iodoplatinate solution

Visualization Dragendorff spray, positive, acidified iodoplatinate solution positive. 

Location reagent acidified iodoplatinate solution oversprayed the plate, giving a positive color, with Rf value of 70. 

Analyte Rf value 37 (acidified iodoplatinate solution, positive) [2, 64],... 

Location Reagents. Spray file plate developed m System TA, and one of file plates developed in System TE, with acidified iodoplatinate solution. Lightly spray the remaining plate developed in System TE with 9M sulphuric acid phenothiazine drugs and tiieir metabolites give pink, red, or blue spots. Overspray with acidified iodoplatinate solution the presence of the acid deepens the blue colour produced when morphine reacts with iodoplatinate solution, and this increases the sensitivity of detection of this compound. 

Cocaine gives a bright blue colour with acidified iodoplatinate solution, and has the same Rf value as methadone in System TE the two are well separated in System TA. In practice, cocaine is rarely detected in urine samples by this technique. The drug is rapidly metabolised to benzoylecgonine, a polar substance which extracts poorly into organic solvents. Immunoassay kits which are highly specific for benzoylecgonine are available, and this method should be used if it is essential to detect cocaine abuse. 

This drug gives two spots which have a distinctive appearance on the TLC plate. These spots are due to the drug itself and its metabolite, nordihydrocodeine, both of which react with acidified iodoplatinate solution to give deep brown-violet spots. 

Methadone is AT-demefiiylated in the body to give a product which imdergoes spontaneous cycHsationto yield two metabohtes in the urine. In System TE, methadone and the metabolites run almost coincidentally on file solvent fi ont, whereas in System TA, methadone nms just above morphine and is separated from the metabohtes which run at about Rf 15. Both methadone Mid the metabolites give characteristic red-violet colours with acidified iodoplatinate solution. Mefiiadone and the metabohtes are usuaUy found in most samples, but occasionally only the metabolites M-e detected. 

Location Reagents. For Systems TN and TO. Acidified iodoplatinate solution, Violet, blue-violet, grey-violet, or brown-violet spots on a pink background are given by quaternary ammonium compounds. 

Thin-layer Chromatography. System TA—Rf system TB—Rf 03 system TC—Rf 25. Dragendorffspray, positive FPN reagent, pink acidified iodoplatinate solution, positive Marquis reagent, orange.)... 

Thin-layer Chromatography. System TA—Rf 24 system TB—Rf 00 system TC—Rf 01. (Acidified iodoplatinate solution, strong reaction.)... 

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