A Novel On‐Chip Method for Differential Extraction of Sperm in Forensic Cases

One out of every six American women has been the victim of a sexual assault in their lifetime. However, the DNA casework backlog continues to increase outpacing the nation\u27s capacity since DNA evidence processing in sexual assault casework remains a bottleneck due to laborious and time‐consuming differential extraction of victim\u27s and perpetrator\u27s cells. Additionally, a significant amount (60–90%) of male DNA evidence may be lost with existing procedures. Here, a microfluidic method is developed that selectively captures sperm using a unique oligosaccharide sequence (Sialyl‐LewisX), a major carbohydrate ligand for sperm‐egg binding. This method is validated with forensic mock samples dating back to 2003, resulting in 70–92% sperm capture efficiency and a 60–92% reduction in epithelial fraction. Captured sperm are then lysed on‐chip and sperm DNA is isolated. This method reduces assay‐time from 8 h to 80 min, providing an inexpensive alternative to current differential extraction techniques, accelerating identification of suspects and advancing public safety

Microtron Irradiation Induced Tuning of Band Gap and Photoresponse of Al-ZnO Thin Films Synthesized by mSILAR

Al-doped polycrystalline nano ZnO (Al-ZnO) thin films with different doping concentrations were successfully prepared by the microwave-assisted successive ionic layer adsorption and reaction (mSILAR) technique. The structural analysis along with the orientation of the prepared films was examined by powder x-ray diffraction (PXRD) patterns. The deposited film is polycrystalline and the (002) orientation enhanced upon doping. Additional investigations were carried out to study the effect of electron beam irradiation (e−-irradiation) on the band gap and photoconductivity of both irradiated and unirradiated samples. Both the Al doping and e−-irradiation led to the enhancement of the photoconductivity of prepared materials. This property enables us to tune the properties of materials for various applications by controlling dopant concentrations and e−-irradiation. The dependence of photocurrent on e−-irradiation of Al-ZnO thin films was not reported previously. Therefore, Al-doped polycrystalline nano-ZnO thin film is a promising material for band gap engineering and for the development of solar cells