Detection of prostate specific antigen by ELISA

Area of Science:

• Forensic Science
• Biochemistry
• Immunology

Background:

• Accurate identification of semen is crucial in forensic investigations.
• Existing methods for semen detection have limitations.
• Prostate specific antigen (PSA) is a key biomarker for semen.

Purpose of the Study:

• To develop and validate a sensitive and specific enzyme-linked immunosorbent assay (ELISA) for prostate specific antigen (PSA) detection.
• To evaluate the method's performance in identifying semen in forensic casework samples.
• To compare the ELISA method with other semen identification techniques.

Main Methods:

• Development of an enzyme-linked immunosorbent assay (ELISA) for prostate specific antigen (PSA) detection.
• Evaluation of the assay's sensitivity, achieving detection levels below 1 ng/mL PSA.
• Testing for specificity against various domestic contaminants and body fluids.
• Assessment of the method's performance on casework samples, including analysis of potential sources of false-negative results (e.g., detergent contamination, poor sample preservation).

Main Results:

• The developed ELISA method demonstrated high sensitivity, routinely achieving detection limits below 1 ng/mL PSA.
• The assay showed high specificity, with no false-positive results observed from tested domestic contaminants and body fluids.
• False-negative results were noted in samples contaminated with detergents and in some poorly preserved evidence.
• Comparison with other methods indicated the ELISA's efficiency for semen identification in forensic casework.

Conclusions:

• The developed ELISA method is a highly sensitive and specific tool for the identification of semen in forensic casework.
• The method offers an efficient alternative for PSA detection, despite minor limitations related to sample contamination and preservation.
• Further research may be warranted to mitigate the impact of detergents and improve performance with aged samples.