(335b) Gel-Preloaded Microchips for DNA Analysis

DNA analysis is one of the most important techniques used in analytical chemistry, life science research and medical diagnostics. Besides the conventional slab gel electrophoresis, capillary electrophoresis for DNA analysis on microchips has been gaining tremendous attention due to its reduced reagent consumption, fast analysis, high throughput and ease of integration. Various approaches have been adopted or demonstrated to perform DNA analysis such as using polymer solution or cross-linked polymer gel as sieving matrices, applying end-labeled free-solution electrophoresis (ELFSE), creating entropic effect through constructing nanopillars, utilizing a confined suspension of superparamagnetic particles to form self-assembling arrays of posts through the magnetic field, and so on. Among them, using photopolymerized cross-linked gels as the sieving matrix provides several advantages such as easy loading of the monomer solution, short curing time, short separation length and lower electric power required. However, the UV curing system and procedure are demanded. Furthermore, absorption of UV light by some polymers limits the material selection when fabricating plastic microchips. In order to resolve this issue and make the microchips a step further toward being portable, ready-to-use and user-friendly, microchips preloaded with the cross-linked gel for DNA analysis are fabricated and the users only need to load the buffer solution right before conducting DNA analysis. In this presentation, first, the fabrication technique will be described, followed by discussing the processing conditions and polymer film deformation. The cross-linked gels inside the microchannels before and after swelling will also be characterized. Finally, the performance of DNA separation using microchips as fabricated will be examined.