Quantitative investigation of the influence of gold nanoparticles on the dynamics of DNA hybridization using a programmed multi-channel quartz crystal microbalance system

This paper describes a quantitative investigation of the influence of gold nanoparticles (AuNPs) on DNA hybridization using a programmed multi-channel quartz crystal microbalance (QCM) device. This system has the benefit of continuous deposition, adsorption, washing, and drying of samples automatically, which saves time and enhances the accuracy of QCM measurements. A demonstration of the hybridization study has been carried out using a DNA fragment of the P53 gene near codon 248. The results demonstrated that the reliability and hybridization sensitivity of the QCM could be significantly improved by introducing AuNPs. The study revealed a significant increase in the apparent hybridization constant (KD−1 of 5.29 × 1010 M−1) with the addition of AuNPs, compared to those obtained without addition of AuNPs (about 107 M−1); this effect has not been reported before. The results of the experiment indicate the advantage of the multi-channel QCM chip in studying complicated DNA fixation and hybridization, the conjugating interaction between biomolecules and nanoparticles, and the hybridization dynamics.