The Effect Of Gold Nanoparticles On Polymerase Chain Reaction And The Mechanism Research

Polymerase Chain Reaction (PCR) is one of the most popular and important technologies in biology and medicine. DNA molecules can be amplified by this technique, and can be used for futher analysis. With the developement of nanotechnology and it combines with biological techniques, it meet with a chance for ravel out some inconveniences in biological techniques. In this paper, we study the effect of gold nanoparticles on the polymerase chain reaction (PCR) and investigate its mechanism. The results suggest that:1. Gold nanoparticles tend to inhibit the PCR, and the inhibition depend on the amount of gold nanoparticles. The more the amount of gold nanoparticles was used, the little the amplification yields were harvested.2. Increasing Taq DNA polymerase can eliminate the inhibitory effect of PCR, while increasing any other PCR ingredients (Mg²⁺,dNTP,primer,DNA template) can not work.3. Although the inhibitory effect can be reversed by increasing Taq DNA polymerase, the PCR is suppressed again by addition of more gold nanoparticles. When increasing Taq DNA polymerase, the inhibitory effect can be removed once again. Thus the inhibitory effect is caused by the interaction between gold nanoparticles and Taq DNA polymerase.4. The inhibitory effect can be reversed by adding bovine serum albumin (BSA).It indicates that BSA and Taq DNA polymerase interact with gold nanoparticles competitively.5. The results of UV-vis spectrum, distributing spectra respectively shows that the absorption spectrum shifts from 518nm to 527nm, the gold nanoparticles become larger,and and X-ray phtoelectronic spectrum (XPS) appears Au and N peak, those indicated that both BSA and Taq DNA polymerase interacted with gold nanoparticles.6. The circular dichroism (CD) data shows that the conformation of BSA is changed after conjugation,and the conformation change is bigger at higher concentrations of gold nanoparticles.7. We propose the possible mechanism that gold nanoparticles effect PCR: the conformation of Taq DNA polymerase could be changed by gold nanoparticles,the activity of polymerase may be decreased, leading to suppression of PCR.