Department of Chemistry, Fudan University, Shanghai 200433, China.
Nanoscale. 2015 Oct 7;7(37):15191-6. doi: 10.1039/c5nr04498g.
Protein-nanoparticle interactions are important in biomedical applications of nanoparticles and for growing biosafety concerns about nanomaterials. In this study, the interactions of four plasma proteins, human serum albumin (HSA), myoglobin (MB), hemoglobin (HB), and trypsin (TRP), with Au and Ag nanoparticles were investigated by FT-IR spectroscopy. The secondary structure of thio-proteins changed with time during incubation with Au and Ag nanoparticles, but the secondary structures of non-thio-proteins remained unchanged. The incubation time for structural changes depended on the sulfur-metal bond energy; the stronger the sulfur-metal energy, the less the time needed. H/D exchange experiments revealed that protein-NP complexes with thio-proteins were less dynamic than free proteins. No measurable dynamic differences were found between free non-thio-proteins and the protein-Au (or Ag) nanoparticle complex. Therefore, the impact of covalent bonds on the protein structure is greater than that of the electrostatic force.
蛋白质-纳米粒子相互作用在纳米粒子的生物医学应用中很重要，并且对纳米材料的生物安全性越来越关注。在这项研究中，通过傅里叶变换红外光谱研究了四种血浆蛋白（人血清白蛋白（HSA）、肌红蛋白（MB）、血红蛋白（HB）和胰蛋白酶（TRP））与 Au 和 Ag 纳米粒子的相互作用。巯基蛋白与 Au 和 Ag 纳米粒子孵育过程中其二级结构随时间发生变化，但非巯基蛋白的二级结构保持不变。结构变化的孵育时间取决于硫-金属键能；硫-金属键能越强，所需时间越短。H/D 交换实验表明，具有巯基蛋白的蛋白质-NP 复合物比游离蛋白的动态性差。在自由非巯基蛋白和蛋白-Au（或 Ag）纳米粒子复合物之间没有发现可测量的动态差异。因此，共价键对蛋白质结构的影响大于静电力。
