ISSN: 0022-1198
CODEN: JFSCA
Page Count: 6

Validation Studies of an Immunochromatographic 1-Step Test for the Forensic Identification of Human Blood
Cordier, A
Commander, Police Forensic Laboratory Aarau,

Budowle, B
Program manager for DNA Research, FSRTC, FBI Academy, VA

Gehrig, C
Forensic scientists and director, Institute of Legal Medicine, University of Bern,

Schmidt, L
Police Forensic Laboratory Bern,

Hochmeister, MN
Forensic scientists and director, Institute of Legal Medicine, University of Bern,

Thali, M
Forensic scientists and director, Institute of Legal Medicine, University of Bern,

Rudin, O
Forensic scientists and director, Institute of Legal Medicine, University of Bern,

Dirnhofer, R
Forensic scientists and director, Institute of Legal Medicine, University of Bern,

Sparkes, R
Senior forensic scientist, Forensic Science Service,

(Received 11 June 1998; accepted 8 September 1998)

Abstract

An immunochromatographic 1-step test for the detection of fecal occult blood was evaluated for applicability for the forensic identification of human blood in stained material. The following experiments were conducted: 1) determination of the sensitivity and specificity of the assay; 2) evaluation of different extraction media for bloodstains (sterile water, Tris buffer pH 7.5 provided in the test kit, 5% ammonia); 3) analysis of biological samples subjected to a variety of environmental insults; and 4) evaluation of casework samples.

This immunochromatographic 1-step occult blood test is specific for human (primate) hemoglobin and is at least an order of magnitude more sensitive than previous methods for detecting human hemoglobin in bloodstains. The antigen is insensitive to a variety of environmental insults, except for exposure to certain detergents and household bleaches and prolonged exposure to certain preparations of luminol.

The entire assay can be conducted in field testing conditions within minutes. When in the laboratory the supernatant from a DNA extraction is used for the assay, there is essentially no consumption of DNA for determining the presence of human hemoglobin in a forensic sample. The data demonstrate that this test is robust and suitable for forensic analyses.

Keywords:
forensic science, hemoglobin, identification, human blood, bloodstains, luminol, species identification, DNA typing, validation studies

Paper ID: JFS14516J
DOI: 10.1520/JFS14516J
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