[Possibility of detecting HBsAG in bloodstains on evidential objects by solid-phase immunoenzyme assay]

This study was designed to detect HBsAg in bloodstains on evidential objects by solid-phase immunoenzyme assay and to characterize its sensitivity, specificity, and reproducibility as well as effect of various external factors on the results of HBsAg measurements. Both whole blood from 25 HBsAg carriers and its stains were available for analysis. HBsAg was detected in all blood stains regardless of the time of their formation. However, HBsAg was absent in 25 stains of blood from control subjects and in 27 extracts from carrier objects. A highly specific, sensitive, and well-reproducible method was developed for determining HBsAg in traces of blood after its preliminary extraction from the stain. The method allows HBsAg to be detected in a stain containing 4 x 10(-6) ml of blood.