Abstract by Robert Hanson
Chemistry and Biochemistry
Capture of drug resistance genes linked to septic shock via sequence specific hybridization in a microfluidic device
Efforts to reduce deaths caused by sepsis would be greatly advanced by the ability to rapidly detect the presence of bacterial drug resistance genes in a blood sample. A novel strategy for probing drug resistance genes is to use a system capable of detecting each molecule individually. A key technical challenge of this approach is ensuring that the captured genes provide an appropriate signal to noise ratio. The focus of our research has been to develop sequence-specific capture of nucleic acids suitable for single molecule detection.
To capture DNA segments that are capable of accepting multiple labels for easy detection, we have utilized magnetic beads modified with a 25 base pair ssDNA complementary to the target sequence. We have been able to capture 500 base pair PCR amplicons of clinical isolates from a 100 µL sample in less than 15 minutes. We have also been able to integrate these methods into a single channel, pressure driven microfluidic system. The device was capable of concentrating 10 femtomoles of target DNA to a level detectable by laser-induced fluorescence. Such technology will be critical in the development of devices used in the diagnosis of sepsis.