Towards dynamic coating of glass microchip chambers for amplifying DNA viathe polymerase chain reaction

As microchip technology evolves to allow for the integration of more comple x processes, particularly the polymerase chain reaction (PCR), it will beco me necessary to define simple approaches for minimizing the effects of surf aces on the chemistry/processes to be performed. We have explored alternati ves to silanization of the glass surface with the use of additives that eit her dynamically coat or adsorb to the glass surface. Polyethylene glycol, p olyvinylpyrrolidone (PVP), and hydroxyethylcellulose (HEC) have been explor ed as potential dynamic coatings and epoxy (poly)dimethylacrylamide (EPDMA) evaluated as an adsorbed coating. By carrying out analysis of the PCR prod ucts generated under different conditions via microchip electrophoresis, we demonstrate that these coating agents adequately passivate the glass surfa ce in a manner that prevents interference with the subsequent PCR process. While several of the agents tested allowed for PCR amplification of DNA in glass, the EPDMA was clearly superior with respect to ease of preparation. However, more efficient PCR (larger mass of amplified product) could be obt ained by silanizing the glass surface.