Abstract: Fresh urine to be tested eventually for detection of abuse-type drugs is preserved at room temperature for as long as six months by adding to the urine a small amount of a methanol solution of methyl and propyl parahydroxybenzoic acids.

Abstract: A method of making drug abuse test papers wherein bibulous paper carriers are impregnated with specific test chemicals, (bismuth subnitrate, potassium iodide, acetic acid, and platinum salt), in two coatings and dried after each coating under specific temperature conditions. The test chemicals are provided for the detection of the drug abuse compounds of amphetamine, cocaine, marijuana, and narcotics contained in low concentrations in animal or human urine. Additionally described is a means of preserving urine samples using esters of parahydroxybenzoic acid.

Abstract: A diagnostic method and indicator for heme in controlled sensitivity is provided by impregnating a bibulous body, such as a test strip with a solution of a color indicator in leuco form and drying and storing in stable active form, and in use applying to the strip a test sample containing heme. The test color is then developed in the strip by wetting the test sample and strip in contact therewith with a peroxide solution of a solvent for the leuco dye carrying the oxygen released from the peroxide by the heme peroxidase in the test sample, such as blood or body tissue or residues containing occult blood whose presence is to be determined.