Submitted to the Department of Chemical Engineering.
Thesis (Ph.D.)--Stanford University, 2013.
Purified DNA serves as a template for a wide array of analysis techniques, ranging from sequencing to PCR and hybridization assays. DNA analysis can be used for clinical diagnosis, for forensic investigation, and for a range of research purposes. These analysis techniques improve each year, but they are all constrained by the availability of purified DNA. DNA is typically derived from raw biological samples that contain a host of other molecular species, including proteins, lipids and metal ions. These species can inhibit analysis of the DNA, so purification of DNA from complex sample matrices is a necessary precursor to analysis. Typically, DNA purification is performed using either liquid-liquid extraction or solid-phase extraction, both of which require manual labor, involve toxic chemicals, and are difficult to miniaturize. Isotachophoresis (ITP) is an alternative method for DNA purification that does not rely on specialized surface chemistry or toxic chemical species. Instead, ITP uses electric fields to selectively pre-concentrate DNA from a raw sample, and simultaneously separate it from inhibiting species. ITP purification of DNA has been demonstrated from human serum, plasma, and whole blood, and the same technique has been used to purify RNA from bacteria in human blood and urine. Until recently, the parameters governing extraction efficiency, throughput, and separation quality in ITP purification were not well established. This thesis is focused on rational analysis for designing and optimizing ITP systems for rapid, high quality DNA purification.