A rotationally-driven dynamic solid phase sodium bisulfite conversion disc for forensic epigenetic sample preparation

Area of Science:

• Forensic Science
• Molecular Biology
• Biotechnology

Background:

• Current forensic human identification (HID) relies on comparing DNA profiles, often failing when reference samples are unavailable or no database match is found.
• Epigenetic analysis offers an alternative for HID, but traditional sodium bisulfite conversion (BSC) is time-consuming, labor-intensive, and causes DNA degradation.

Purpose of the Study:

• To develop a more efficient and integrated sample preparation method for epigenetic analysis in forensic DNA workflows.
• To introduce a microfluidic-based dynamic solid-phase bisulfite conversion (dSP-BSC) as an alternative to conventional BSC.

Main Methods:

• Development of a rotationally-driven, microfluidic system for dynamic solid-phase bisulfite conversion (dSP-BSC).
• Automated parallel processing of up to four samples.
• Assessment of DNA recovery, conversion efficiency, and incubation time compared to gold-standard and enzymatic methods.

Main Results:

• The dSP-BSC method significantly decreased incubation intervals by approximately 36%.
• The microfluidic approach streamlines the sample preparation process, making it more amenable to forensic DNA workflows.
• Evaluated relative DNA recovery and conversion efficiency against established methods.

Conclusions:

• The developed microfluidic dSP-BSC method offers a faster, automated, and potentially less damaging alternative for epigenetic analysis in forensic human identification.
• This innovation could enhance the utility of epigenetic data for forensic investigations, especially in challenging cases lacking traditional DNA profile matches.