Learn More
A silica-based solid-phase extraction system suitable for incorporation into a microchip platform (nu-total analytical system; nu-TAS) would find utility in a variety of genetic analysis protocols, including DNA sequencing. The extraction procedure utilized is based on adsorption of the DNA onto bare silica. The procedure involves three steps: (i) DNA(More)
The current understanding of insect cell metabolism is very limited. In order to gain some insight into the growth and metabolism of insect cells Spodoptera frugiperda (Sf9), a comprehensive characterization of culture conditions for cells grown in the IPL-41 medium was made by measuring the amino acid composition of the growth medium and the cell extract,(More)
A novel DNA solid-phase extraction protocol based on the pH-dependent charge of chitosan was developed specifically for low-volume DNA extraction on microchips. The method uses chitosan-coated beads to extract DNA at pH 5 and release it from the chitosan at pH 9. DNA extraction efficiency as high as 92% could be attained, even from complex samples such as(More)
We describe a microfluidic genetic analysis system that represents a previously undescribed integrated microfluidic device capable of accepting whole blood as a crude biological sample with the endpoint generation of a genetic profile. Upon loading the sample, the glass microfluidic genetic analysis system device carries out on-chip DNA purification and(More)
There is much interest in developing methods amenable to amplifying nucleic acids by the polymerase chain reaction (PCR) in small volumes in microfabricated devices. The use of infrared-mediated temperature control to accurately thermocycle microliter volumes in microchips fabricated from polyimide is demonstrated. Amplification of a 500-base-pair fragment(More)
A microchip solid-phase extraction method for purification of DNA from biological samples, such as blood, is demonstrated. Silica beads were packed into glass microchips and the beads immobilized with sol-gel to provide a stable and reproducible solid phase onto which DNA could be adsorbed. Optimization of the DNA loading conditions established a higher DNA(More)
The current backlog of casework is among the most significant challenges facing crime laboratories at this time. While the development of next-generation microchip-based technology for expedited forensic casework analysis offers one solution to this problem, this will require the adaptation of manual, large-volume, benchtop chemistry to small volume(More)
Forensic DNA analysis of sexual assault evidence requires separation of DNA from epithelial (victim) and sperm (perpetrator) cells. The conventional method used by crime laboratories, which is termed "differential extraction", is a time-consuming process. To supplant the conventional process, separation of sperm from a biological mixture containing(More)
This report focuses on the development of a method for chemically induced enhancement of cell elution and recovery from cotton swabs. The method exploits the exclusive use of detergents for intact cell removal, and can be utilized in conjunction with, or to circumvent, conventional differential extraction (DE). Samples treated with Sarkosyl (54.4 +/- 1.8%)(More)
Effective microchip extraction of deoxyribonucleic acid (DNA) from crude biological matrixes has been demonstrated using silica beads or hybrid phases composed of beads and sol-gel. However, the use of monolithic sol-gels alone for extraction of human genomic DNA has been more difficult to define. Here we describe, for the first time, the successful use of(More)