Abstract
OC-Hemocatch, an immunochromatographic test device for fecal occult blood, has been used for the forensic identification of human blood. False-positive and false-negative effects by detergents and disinfectants on detection of human blood using OC-Hemocatch were investigated in this study. Dishwashing and laundry detergents showed no false-positive but false-negative results. Four in 8 disinfectants showed false-positive results, and 3 in the other 4 disinfectants inhibited the detection of human blood. Cationic and anionic surfactants showed false-positive results, but non-ionic and amphoteric surfactants did not, suggesting that the antibody-conjugated blue latex particles were aggregated electrically by cations or anions and caught nonspecifically onto the detection line. False-negative results might be caused by denaturation or degradation of hemoglobin by the comtaminants.
