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Automation of Differential Extraction With Sperm Quantitation Using Microfluidic-lntegrated Shadow Imaging System for Forensic Applications

NCJ Number
Date Published
Utkan Demirci, Margery Corbett
Findings and methodology are reported for a project that developed a microfluidic method that selectively captures sperm by using a unique oligosaccharide sequence (Sialyl LewisX), which is a major carbohydrate ligand for sperm-egg binding.
This method was validated with forensic mock samples that dated back to 2003, resulting in 70-92 percent sperm capture efficiency and a 60-92 percent reduction in epithelial fraction. Captured sperm were then lysed on-chip and DNA was isolated. This method reduces assay time from 8 hours to 80 minutes, thus providing an inexpensive alternative to current differential extraction techniques. This accelerates the identification of suspects in sexual assault cases and facilitates a reduction in the backlogs of untested sexual assault kits that are widespread among U.S. law enforcement agencies, given the prevalence of the sexual victimization of women in America (one out of every six women is sexually victimized in her lifetime). Recommendations are offered for additional research that may further reduce the processing time for sexual-assault evidence. 5 figures, 1 table, and 38 references
Date Created: January 15, 2019