Mass screening and confirmation of phencyclidine (PCP) in urine by radioimmunoassay/TLC.

A sensitive, rapid, and specific procedure is described for the mass screening and confirmation of PCP (phencyclidine) in urine specimens at concentrations as low as 0.3 microgram of PCP per mL. Specimens that test positive by radioimmunoassay must be confirmed by TLC using methylene chloride:n-butanol:concentrated NH4OH (85:15:0.5) as the developing solvent system. This separates PCP from other drugs or endogenous urinary substances.