Validation Studies of ‘OC-Hemocatch’ for the Forensic Identification of Human Blood

Abstract

  ‘OC-Hemocatch’, an immunochromatographic test for the detection of fecal occult blood was evaluated for the forensic identification of human blood. ‘OC-Hemocatch’ showed positive results for human blood to a dilution of 1:500,000 and provides the strongest detection line for a dilution of 1:20,000. On the other hand, the human blood diluted to 1:100 was negative for ‘OC-Hemocatch’ because of the high dose hook effect. While heating at over 150°C, long term exposing to sunlight, washing and bleaching of bloodstains prevented the detecting of human hemoglobin using ‘OC-Hemocatch’, contamination of blood with various body fluids did not affect it. Furthermore, ‘OC-Hemocatch’ detected human hemoglobin from old bloodstains stored for 15 years at room temperature when 5% ammonia was used for extraction. These results demonstrate that ‘OC-Hemocatch’ can be effectively applied to forensic identification of human blood.