Department of Forensic Sciences, Punjabi University, Patiala - 147002.
Two hundred bloodstains prepared on cotton cloth of knows blood group of different ages (4–5 hours, 7,15,21 and 28 days were examined for ABO (H) antigens detection after washing with cold and hot water for a varied length of time (15, 30, 45 and 60 minutes) by different techniques - absorption inhibition (AI), mixed agglutination (MA), simple absorption elution (AE) and absorption elution using LISS. Bloodstains washed with hot water can be typed more easily for the ABO (H) antigens with all the techniques used while it was difficult to detect after washing the stains with cold water in comparison. In this investigation the detection of ABO (H) antigens by absorption elution using low ionic strength solution has been found to be more suitable and reliable. The age of the stain, procedure adopted and time used for washing are important factors in the detection of ABO (H) antigens.
