Coomassie Brilliant Blue G-250 Dye: New Application for Forensic Fingerprint Analysis.

The Bradford reagent, comprised of the Coomassie Brilliant Blue G-250 dye, methanol and phosphoric acid, has been traditionally used for quantifying proteins. Use of this reagent in the Bradford assay relies on the binding of the Coomassie Blue G-250 dye to proteins. However, the ability of the dye to react with a small group of amino acids - arginine, histidine, lysine, phenylalanine, tyrosine, and tryptophan - makes it a viable chemical assay for fingerprint analysis in order to identify the biological sex of the fingerprint originator. It is recognized that the identification of biological sex has been readily accomplished using two other methods, however, both of those systems are reliant upon a large group of amino acids - 23 to be precise. The Bradford assay, described here, was developed specifically to aid in the transition from targeting large groups of amino acids, as demonstrated in the previous studies, to targeting only a single amino acid without compromising the intensity of the response and or the ability to differentiate between two attributes - in this case, female fingerprints from male fingerprints.