This work describes the development of a novel microdevice for forensic DNA processing of reference swabs. This microdevice incorporates an enzyme‐based assay for DNA preparation, which allows for faster processing times and reduced sample handling. Infrared‐mediated PCR (IR‐PCR) is used for STR amplification using a custom reaction mixture, allowing for amplification of STR loci in 45 min while circumventing the limitations of traditional block thermocyclers. Uniquely positioned valves coupled with a simple rotational platform are used to exert fluidic control, eliminating the need for bulky external equipment. All microdevices were fabricated using laser ablation and thermal bonding of PMMA layers. Using this microdevice, the enzyme‐mediated DNA liberation module produced DNA yields similar to or higher than those produced using the traditional (tube‐based) protocol. Initial microdevice IR‐PCR experiments to test the amplification module and reaction (using Phusion Flash/SpeedSTAR) generated near‐full profiles that suffered from interlocus peak imbalance and poor adenylation (significant −A). However, subsequent attempts using KAPA 2G and Pfu Ultra polymerases generated full STR profiles with improved interlocus balance and the expected adenylated product. A fully integrated run designed to test microfluidic control successfully generated CE‐ready STR amplicons in less than 2 h (<1 h of hands‐on time). Using this approach, high‐quality STR profiles were developed that were consistent with those produced using conventional DNA purification and STR amplification methods. This method is a smaller, more elegant solution than current microdevice methods and offers a cheaper, hands‐free, closed‐system alternative to traditional forensic methods.

View Resource will open in new tab

Related Products

forensicGEM Universal

MicroGEM's forensicGEM Universal Kit provides users with a single tube solution for extracting DNA from a variety of forensically-relevant human samples.

Extracts DNA from forensic samples including saliva (liquid, swab, stains, storage card – FTA), blood (liquid, swab, stains, storage card – FTA), and tissue (solid, hair).

Produces high-quality single-stranded DNA proven for use with STR, PCR, qPCR and whole genome amplification.

Each kit contains forensicGEM, Histosolv, BLUE buffer, RED+ buffer and ORANGE+ buffer.

View Product