Enzyme Linked Immunosorbent Assay (ELISA) screening techniques are widely utilized by toxicologists to screen forensic specimens for drugs of abuse. These immunoassays are extremely flexible and have adequate sensitivity to go down to the drug levels found in most forensic matrices.

• ANTIBODY IS IMMOBILIZED ON MICRO-PLATE WELLS
• COMPETITION BETWEEN DRUG IN FORENSIC SAMPLE AND ENZYME LABELED DRUG FOR ANTIBODY BINDING SITES
• THE UNBOUND MATERIAL IS WASHED OUT.
• CHROMOGENIC SUBSTRATE ADDED TO DEVELOP COLOR WITH BOUND ENZYME
• RESULTING COLOR IS READ IN A SPECTROPHOTOMETER

PRINCIPLE OF ELISA

ADVANTAGES OF ELISAS

• Heterogeneous Assays
• Oriented Antibody:
• Optimal Enzyme conjugates.
• Small sample size:
• Long shelf life: All Immunalysis ELISA kits have a minimum shelf life of one year. “Ready to use” reagents:
• Non isotopic:
• No azide or mercury preservatives

• Lends itself to different levels of automation