Molecular Interactions between Gold Nanoparticles and Model Cell Membranes: A Study of Nanoparticle Surface Charge Effect

作者：Hu Peipei; Qian Wei; Liu Bing; Pichan Cayla; Chen Zhan^*

来源：Journal of Physical Chemistry C, 2016, 120(39): 22718-22729.

DOI：10.1021/acs.jpcc.6b07565

Surface modification of nanoparticles (NPs) has been reported to play a significant role in determining their interactions with cell membranes. In this research, the interactions between carboxyl- or amine-functionalized Au NPs and model mammalian cell membranes were investigated by a nonlinear optical spectroscopic technique, sum frequency generation (SFG) vibrational spectroscopy, supplemented by attenuated total reflection-Fourier transform infrared (ATR-FTIR) spectroscopy. To test the effects of surface composition on the NP-membrane interactions, we altered the ratio of different functional groups on the NP surfaces to create NPs with varied surface chemistry. In this study, a substrate-supported 1,2-distearoyl-d(70)-sn-glycero-3-phosphocholine (d(70)-DSPC or dDSPC)/1,2-distearoyl-sn-glycero-3-phosphocholine (DSPC) lipid bilayer was used as a model cell membrane. It was found that the interactions between the Au NPs and the lipid bilayer induced the lipid bilayer to flip-flop. A higher surface coverage of carboxyl functional groups on Au NPs tends to induce lipid flip-flop at a higher rate. For amine-functionalized NPs, a lower interaction rate was found in most cases for NPs with higher surface coverage. The pH of the Au NP solution also influences the Au NP-lipid bilayer interactions. Our study provides a quantitative method for assessing the interactions between a model mammalian cell membrane and Au NPs with different surface functional groups, namely, amine or carboxyl groups, in Au NP solutions with different pH values.

• 出版日期2016-10-6