Effects of single-walled carbon nanotubes on the polymerase chain reaction

Abstract

The effects of single-walled carbon nanotubes on the polymerase chain reaction(PCR) were investigated via quantitative PCR product measurements, scanningelectron microscopy (SEM), high-resolution transmission electron microscopy(TEM) and x-ray photoelectron spectroscopy (XPS). The results showed thatadding single-walled carbon nanotubes (SWCNTs) into the reaction liquidincreases the amount of PCR product at SWCNT concentrations below3 µg µl−1,but this effect is reversed at higher SWCNT concentrations.Similar effects were observed in PCR reactions with or withoutMg2+.Both SEM and HRTEM results showed that the DNA templates and Taq enzymes areattached to bundles of SWCNTs in PCR products. XPS results showed that the C 1sbinding energy in PCR products increased after reaction, with the emergence of two newpeaks beside the main peak compared with carbon nanotubes before reaction, suggestingthat there might be a chemical reaction between SWCNTs and PCR components. Inconclusion, SWCNTs may increase the PCR efficiency at a concentration range of less than3 µg µl−1 in the reaction liquid and have the potential to act as catalysts in a variety of biochemicalreactions.