Abstract
Aminobenzylpenicilloic acid, which is transformed from ampicillin readily in alkaline solution, forms an intensive and reproducible fluorescent product in neutral solution containing mercuric chloride under the condition of 40°. The fluorescent product has uncorrected excitation and emission maxima at 340 and 420 nm, respectively, and this compound is readily extracted into ethyl acetate and chloroform from acidic and neutral media and then can be back extracted into alkaline media. An assay product based on these observations permits detection of less than 0.1 μg/ml of ampicillin and/or aminobenzylpenicilloic acid. The fluorescent product is not formed from ampicillin directly, so that the direct separate measurement can be made of aminobenzylpenicilloic acid as well as unchanged ampicillin in aqueous solution, urine and blood.
