Probing Amino Acid Interaction with a Polystyrene Nanoparticle Surface Using Saturation-Transfer Difference (STD)-NMR
Probing Amino Acid Interaction with a Polystyrene Nanoparticle Surface Using Saturation-Transfer Difference (STD)-NMR
复制标题
使用饱和传递差 (STD)-NMR 探测氨基酸与聚苯乙烯纳米颗粒表面的相互作用
DOI：
10.1021/acs.jpclett.8b02785
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发表时间：
2018
期刊：
影响因子：
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通讯作者：
Casabianca, Leah B.
中科院分区：
文献类型：
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作者：
Zhang, Yunzhi;Casabianca, Leah B.
用饱和转移差分(STD)-核磁共振(NMR)研究了溶液中单个氨基酸与羧酸修饰聚苯乙烯纳米颗粒表面的相互作用。在固定的饱和时间通过STD-核磁共振实验筛选单个氨基酸的纳米颗粒结合，并测量在初始筛选中显示显著STD差异信号的氨基酸的STD累积曲线。芳香族侧链上的质子的STD效应最强，长链脂肪族和带正电的侧链上的质子的STD效应相对较弱。这表明这些聚苯乙烯纳米粒子有几种结合方式：羧酸修饰的聚苯乙烯纳米粒子的负电荷表面与带正电的氨基酸之间的静电吸引，长脂肪侧链与纳米粒子表面之间的疏水作用，以及芳香族氨基酸与苯乙烯中芳香族基团之间的π-π相互作用。这一信息可用于未来的研究，以预测和了解纳米颗粒表面与小肽和蛋白质中特定氨基酸残基之间的相互作用。
The interaction between individual amino acids and the surface of carboxylate-modified polystyrene nanoparticles in solution was studied using Saturation-Transfer Difference (STD)–Nuclear Magnetic Resonance (NMR). Individual amino acids were screened for nanoparticle binding using an STD-NMR experiment at a fixed saturation time, and STD buildup curves were measured for those amino acids that exhibited significant STD difference signals in the initial screening. The strongest STD effects were measured for protons of aromatic side chains, with relatively weaker effects observed for protons in long-chain aliphatic and positively charged side chains. This indicates that there are several modes of binding to these polystyrene nanoparticles: electrostatic attraction between the negatively charged surface of the carboxylate-modified polystyrene nanoparticle and positively charged amino acids, hydrophobic effects between long aliphatic side chains and the nanoparticle surface, and π–π interactions between aromatic amino acids and aromatic groups in styrene. This information can be used in future studies to predict and understand interactions between nanoparticle surfaces and specific amino acid residues in small peptides and proteins.