Comparison of presumptive blood test kits including Hexagon OBTI

Hochmeister et al. (1) performed validation tests for the Hexagon OBTI kit in 1999 and found a sensitivity of 1:100,000 when diluted in sterile water, a magnitude more sensitive than found in the current study under standard conditions. Hochmeister et al. (1) also conducted specificity, degradation, and contamination studies and determined that there was no effect on DNA recovery. This study was complimented by the work of Hermon et al. (2) who determined that sensitivity could be increased with a reduction of the buffer solution from 2 mL to 200 lL and also with an increase in incubation time. The maximum sensitivity that Hermon et al. (2) achieved was 1:1,000, even with an increase in incubation times, which they attribute to different volumes of blood used for the initial sampling. They also tested the specificity of the assay using different species of animals as well as other human body fluids.