SBIR-STTR Award

The presence of penicillin residues in milk has posed a long-standing health problem for consumers and an economic problem for dairy producers and milk processors. Current methodologies used to detect these residues do not possess the attributes consistent for testing of milk at all stages of production and processing. The applicability of DDX's OpTest technology for the detection of penicillin residues in milk will be evaluated by defining the physical and chemical characteristics of the ellipsometric assay components. The tasks will include the selection of ligand(s), determination of attachment chemistries, evaluation of strategies to curb non-specific binding problems, and optimization of the ellipsometry instrument. Successful completion of these objectives will yield a test of high sensitivity and specificity which has the inherent versatility sufficient for use at all stages of milk production, where the detection of penicillin residues is important for both health and economic reasons. A full quantitative report will compare OpTest to current screening methods.

Anticipated Results:
The OpTest for penicillin will serve as the prototype diagnostic test that will introduce a universally usable, highly sensitive, rapid through-put assay system that will fulfill the diagnostic needs at all levels within the dairy industry.

The presence of penicillin residues in milk has posed a long-standing health problem for consumers and an economic problem for dairy producers and milk processors. Current methodologies used to detect these residues do not possess the attributes necessary for testing of milk at all stages of production and processing. The applicability of DDX's OpTest technology for the detection of penicillin residues in milk has been demonstrated in a successful Phase I USDA SBIR supported program, yielding a test of high sensitivity and specificity that also inherently exhibits user-friendly versatility sufficient for use at all stages of milk production. This proposal expands the scope of research on this method, specifically focusing on the issues of ligand immobilization, assay sensitivity, assay dynamic range, signal/mass enhancement, and small "field reader" instrument development. Specific tasks will include further refinement of the selection of ligand(s), selection of high functionality surface attachment chemistries, continued evaluation of the importance of nonspecific binding problems in the milk sample matrix, and continuing optimization and miniaturization of the ellipsometry instrument. A full quantitative report will compare OpTest to current screening and diagnostic methods.

Anticipated Results:
The lack of availability of an economical testing method for antibiotic residues that can be performed and interpreted at all levels of production and distribution within the dairy industry creates serious safety, regulatory compliance, and operational management problems. The OpTest for penicillin, already shown to be both feasible and highly sensitive, will serve as the prototype diagnostic test introducing a universally usable, sensitive, rapid throughput assay system. It is expected that this system will fulfill multiple diagnostic needs at all levels within the dairy and other food producing industries.