[Specimen preparation for ABO determination of various kinds of blood stains]

Trying to optimize the preparation of blood stains, we found methanol fixation not to produce very good results for the determination of ABO blood group antigens. It is advantageous to transfer blood stains before testing to cotton cloth. This transfer is also of practical use if blood stains are to be saved on a smooth surface for lateral determination. We testet on 35 different carrier materials, on which blood stains in casework often were found, whether blood grouping gave better results on either the original material or after transfer. Results are shown on a table. The test revealed, that solubility of the stain in aqua dest is a good sign for a successful transfer. Blood stains on pine-wood soil, soil and loam were not suited for ABO grouping.