A screening method for urinary methamphetamine--latex agglutination inhibition reaction test

Methamphetamine in urine samples from abusers was detected by the latex agglutination inhibition reaction test with latex-antibody (Latex-Ab) and latex-methamphetamine (Latex-MA) reagents. Anti-methamphetamine antibody was produced in rabbits by immunization with bovine serum albumin (BSA)-methamphetamine conjugate. Latex particles were coated with antibodies or with rabbit serum albumin (RSA)-methamphetamine conjugate to obtain Latex-Ab and Latex-MA reagents, respectively. The results are read at 4-5 min after mixing the latex reagents. The sensitivity of this method for methamphetamine was 0.4 micrograms/ml urine. Methamphetamine analogs (methylephedrine, amphetamine, phentermine, methoxyphenamine, ephedrine, beta-phenylethylamine, OH-methamphetamine, OH-amphetamine, and OH-ephedrine) all cross-react in varying degrees, while glucosiurea and albuminurea give false positive results in the tests. Though attention must be paid to these effects this simple and rapid test is suitable for the mass screening of urine samples.