Patent ID: 6949344

Claim:
A method for the identification of marijuana, cocaine, phencyclidine, methamphetamine and opiates from the bloodstream of a subject which becomes embedded in a keratinized structure of the subject which comprises: (a) preparing a mixture comprising a protease suitable for the digestion of keratin, an agent selected from the group consisting of dithiothreitol and dithioerythritol, a biological detergent selected from the group consisting of cholate, deoxycholate, cholic acid, deoxycholic acid, octyl-B-D-glucopyranoside and octyl-B-D-thioglucopyranoside and a sample of keratinized structure; the amounts of said protease, agent and detergent being sufficient to effectuate the digestion of the sample; (b) permitting the digestion of the sample to form a keratin digest solution; (c) ensuring that the protease and the agent will not interfere with the accuracy of an immunoassay method performed on the digest solution; and (d) subjecting a portion of the keratin digest solution to analysis by immunoassay.