Paper BI-ThP12
Chemical Characterization of Taq DNA Polymerase Adsorption on Different Surfaces

Thursday, October 18, 2007, 5:30 pm, Room 4C

PCR (polymerase chain reaction) represents the most widely used method for amplification of defined DNA sequences in medical and biological applications. The most recent innovative technologies are based on PCR reaction miniaturization. In fact, reductions in reagent consumption lower costs and increase scalability, enabling genome-wide approaches. Due to the increased surface-to-volume ratio of microchip PCR, a crucial role is played by the internal surface. Effects related to the non specific surface adsorption of PCR reagents (e.g. the replicating enzyme DNA polymerase) become significant and may reduce the efficiency of DNA amplification. In this study we investigate the Taq (Thermus aquaticus) DNA polymerase adsorption on different material surfaces, namely silicon (with different deposited oxide layer), pyrex glass, chromium nitride, cyclic olefin co-polymer (COC), polycarbonate (PC), poly(methyl methacrylate) (PMMA), and polydimethysiloxane (PDMS) surface. We carry out analyses via time of flight secondary ion mass spectrometry (ToF-SIMS), providing a physical-chemical surface picture, and via immunofluorescence by using anti-Taq DNA polymerase monoclonal antibody, giving the surface distribution and the amount of the protein. By combining these different techniques a deeper insight into the mechanisms governing the non specific surface adsorption of PCR reagents is possible.¹

¹This work was accomplished in the framework of LaTEMAR (Laboratorio di Tecnologie Elettrobiochimiche Miniaturizzate per l'Analisi e la Ricerca - Laboratory of Miniaturized Electrobiochemical Technologies for Analysis and Research), Centre of Excellence funded by MIUR (Italian Ministry for Education, University and Research) grants - FIRB 2003-2004 - for public/private structures involved in research fields characterized by strategic value.