DNA purification silicon chip

A silicon microchip has been developed for purification of deoxyribonucleic acid (DNA) from human blood based on the known affinity of DNA to silica under high chaotropic salt conditions. The chip comprises several components which include a micromixer, microfilter, microbinder and two microvalves to perform the functions of the mixing, filtering, purification and fluidic control; and yet it can be accomplished by a simple mask process flow process. Original human blood sample which is a mixture of many components, including white blood cells (WBC), red blood cells (RBC), platelets, plasma, etc., can be used directly as the input sample. After cell sorting, cell lysing, DNA binding, eluting and cleaning processes, pure DNA has been extracted for the white blood cells. An average of 10 ng DNA/μl blood was able to be extracted from this fully integrated DNA extraction chip. The purity of the eluted DNA was evaluated by optical density at wavelengths of 260 nm and 280 nm. Tests results showed that the most DNA solution eluted was free from RNA and protein contamination.