Separating sperm from cell mixtures by using a bubble-based acoustofluidic filtration device for forensic DNA
Hsiao-Lin Hwa1, Ting-Yu Wan2, Chih-Wen Su3
1Department and Graduate Institute of Forensic Medicine, College of Medicine, National Taiwan University, No. 1, Sec. 1, Jen Ai Rd., Taipei 100, Taiwan; Department of Obstetrics and Gynecology, National Taiwan University Hospital, No. 8 Chung Shan S. Rd., Taipei 100, Taiwan; Department of Medical Genetics, National Taiwan University Hospital, No. 8 Chung Shan S. Rd., Taipei 100, Taiwan.
Forensic Science International. Genetics
|March 25, 2026
Summary
This study shows bubble-based acoustofluidic filtration (BAF) effectively separates sperm from epithelial cells in forensic samples. This improves male DNA contributor identification accuracy in sexual assault investigations.
Area of Science:
- Forensic Science
- Genetics
- Biotechnology
Background:
- Forensic DNA analysis of sperm in sexual assault cases is critical.
- Separating sperm from epithelial cells enhances male DNA contributor analysis.
- Current methods for sperm separation can be challenging.
Purpose of the Study:
- To evaluate the effectiveness of a bubble-based acoustofluidic filtration (BAF) device.
- To assess BAF's ability to separate sperm from epithelial cell mixtures.
- To determine if BAF improves male DNA contributor identification in forensic samples.
Main Methods:
- Sperm separation using a bubble-based acoustofluidic filtration (BAF) device.
- Analysis of two-person and three-person sperm/epithelial cell mixtures.
- Autosomal and Amelogenin short tandem repeat (STR) genotyping.
- Calculation of Amelogenin Y-to-X allele peak height ratios and allele peak height proportions.
- Male contributor assignment using EuroForMix software.
Main Results:
- BAF processing increased Amelogenin Y-to-X allele peak height ratios in 90.6% of two-person and 87.9% of three-person mixtures.
- Mean male-specific allele peak height proportions increased in 96.9% of two-person and 97.0% of three-person mixtures post-BAF.
- Male contributor assignment accuracy improved from 93.8% to 100% for two-person samples and 84.8% to 100% for three-person samples.
Conclusions:
- Bubble-based acoustofluidic filtration (BAF) is effective in separating sperm from epithelial cell mixtures.
- BAF significantly enhances the accuracy of male DNA contributor identification in forensic casework.
- This technology holds promise for improving sexual assault investigations.
Keywords:
Bubble-based acoustofluidic filtrationCell separationMicrofluidic deviceSexual assaultSperm enrichment
