Teichroeb J H, Forrest J A, Jones L W
Department of Physics and Astronomy, Guelph-Waterloo Physics Institute, University of Waterloo, 200 University Ave. W., Waterloo, Ontario N2L 3G1, Canada.
Eur Phys J E Soft Matter. 2008 Aug;26(4):411-5. doi: 10.1140/epje/i2007-10342-9.
We have used localized surface plasmon resonance (LSPR) to monitor the kinetics of thermal denaturing of bovine serum albumin (BSA) adsorbed onto gold nanospheres of size 5 nm-100 nm. The effect of the protein on the LSPR was monitored by visible extinction spectroscopy. The wavelength of the peak extinction (resonance) is affected by the conformation of the adsorbed protein layer, and as such can be used as a very sensitive probe of thermal denaturing that is specific to the adsorbed (as opposed to free) protein. The time dependence of the denaturing is measured in the temperature range 60 degrees C-70 degrees C, and the lifetimes are used to calculate an activation barrier for thermal denaturing. The results show that thermally activated denaturing of proteins adsorbed onto nanoparticles has a nanoparticle-size-dependent activation barrier, and this barrier increases for decreasing particle size. This may have important implications for other protein-nanoparticle interactions.
我们利用局域表面等离子体共振（LSPR）来监测吸附在尺寸为5纳米至100纳米的金纳米球上的牛血清白蛋白（BSA）的热变性动力学。通过可见消光光谱监测蛋白质对LSPR的影响。峰值消光（共振）波长受吸附蛋白层构象的影响，因此可作为对吸附（而非游离）蛋白特异性的热变性非常敏感的探针。在60摄氏度至70摄氏度的温度范围内测量变性的时间依赖性，并利用寿命来计算热变性的活化能垒。结果表明，吸附在纳米颗粒上的蛋白质的热活化变性具有与纳米颗粒尺寸相关的活化能垒，且该能垒随颗粒尺寸减小而增加。这可能对其他蛋白质 - 纳米颗粒相互作用具有重要意义。
