Production and characterisation of antibodies to vanillylmandelic acid

Antibodies were raised to the catecholamine metabolite vanillylmandelic acid (VMA). The side chain was protected and, after derivatisation through the 4-phenolic hydroxyl group, the hapten was coupled to KLH and the resultant conjugate deprotected. Sheep immunised with this immunogen responded with specific, high titre antibodies to VMA as assessed using a fluorescent label. Cross-reaction of the antiserum from one of the sheep was minimal, being under 1% with all naturally occurring related compounds tested. This report is the first to describe an effective antiserum for VMA which will permit measurement over the normal range in urine.