The examination of bloodstains by Laurell electrophoresis (antigen-antibody crossed electrophoresis)

An experimental study of the identification of the person of origin of a bloodstain by crossed immunoelectrophoresis

Crossed immunoelectrophoretic (CIEP) patterns were examined for the purpose of individualization of bloodstains. For comparison the areas of peaks were measured and ratios of the areas of corresponding peaks were calculated. To assess the dispersion of the ratios, the coefficient of variation (CV) was calculated as CV = 100 X standard deviation/mean of ratios. With 1-month-old bloodstains there were significant differences in the distributions of CV between the groups of the same and those of different origin. These results indicate that CIEP is useful as a means of identifying the origin of bloodstains.

Human bloodstains: individualization by crossed electroimmunodiffusion

Crossed electroimmunodiffusion was evaluated as a means for establishing the individuality ("fingerprinting") of human bloodstains. In ten separate examinations on stains from each of ten persons there was at least one peak with a unique range in height so that individualization was possible. The heights of certain peaks showed statistically significant female-male differences.