Purification of Bacillus thuringiensis DNA with polymer-based, microfluidic lab-on-a-chip systems

Aim of the study was to establish and evaluate a “lab-on-a-chip” system for the detection of bacterial B-agents using Bacillus (B.) thuringiensis as simulant for B. anthracis. To enable reliable detection of target DNA using PCR assays it is crucial that purified DNA is extracted from the sample matrix. We established chip-based assays for cell lysis, sample concentration, and DNA purification using magnetic particles with special surface modifications and compared these assays with a commercial routine method. DNA yield was determined using quantitative real-time PCR assays with TaqMan probes targeting the cry1Ac gene. Lab-on-a-chip systems are applicable for point-of-care analysis and provide several advantages in comparison to conventional diagnostic techniques. Purification of DNA and subsequent PCR analysis can be integrated and the instrumentation can be miniaturized. Therefore, such tests can also be useful in medical and veterinary diagnostics.