Lin Hsiao-Chu, Su Yu-An, Liu Ting-Yu, Sheng Yu-Jane, Lin Jiang-Jen
Institute of Polymer Science and Engineering, National Taiwan University, Taipei 10617, Taiwan.
Department of Materials Engineering, Ming Chi University of Technology, New Taipei City 24301, Taiwan.
Colloids Surf B Biointerfaces. 2017 Apr 1;152:459-466. doi: 10.1016/j.colsurfb.2017.01.046. Epub 2017 Jan 27.
The ternary nanohybrids of silver nanoparticles (AgNPs) in combination with silicate nanoplatelets (NSP) and thermally sensitive poly(N-isopropylacrylamide) (PNiPAAm) were fabricated for antibacterial applications. PNiPAAm were chemically grafted on the NSP by atom-transfer radical polymerization (ATRP) via polymerizing N-isopropylacrylamide monomers with sol-gel linkers (BBTES). The nanoparticles of AgNPs then were adsorbed on NSP-PNiPAAm nanosheets through in situ reduction reaction of AgNO in aqueous dispersion. The particle sizes of AgNPs were estimated to be 7-12nm in diameter with different composition ratios of AgNPs to NSP-PNiPAAm, evaluated by transmission electron microscope (TEM). The nanohybrids of AgNP/NSP-PNiPAAm exhibited the unique property of lowest critical solution temperature (LCST) at 32°C. The thermo-responsive antibacterial efficacy of the ternary nanohybrids was demonstrated by Bacillus subtilis (B. subtilis) and Escherichia coli (E. coli) at lower than the LCST (28°C) and higher than the LCST (37°C). The result show that the great antibacterial ability was observed in the hydrophilic bacteria (B. subtilis) at 28°C. In contrast, the excellent antibacterial ability was found in the hydrophobic bacteria (E. coli) at 37°C, due to the surface energy modulation of AgNP/NSP-PNiPAAm. The tailoring of silver-containing ternary nanohybrids allow the new antibacterial nanomaterials to selectively affect the surface of bacteria by varying temperature.
制备了银纳米颗粒（AgNPs）与硅酸盐纳米片（NSP）和热敏性聚（N-异丙基丙烯酰胺）（PNiPAAm）的三元纳米杂化物用于抗菌应用。通过原子转移自由基聚合（ATRP），经由用溶胶-凝胶连接剂（BBTES）聚合N-异丙基丙烯酰胺单体，将PNiPAAm化学接枝到NSP上。然后，通过硝酸银在水分散体中的原位还原反应，将AgNPs纳米颗粒吸附到NSP-PNiPAAm纳米片上。通过透射电子显微镜（TEM）评估，在AgNPs与NSP-PNiPAAm不同组成比的情况下，AgNPs的粒径估计为直径7-12nm。AgNP/NSP-PNiPAAm纳米杂化物在32°C时表现出最低临界溶液温度（LCST）的独特性质。通过枯草芽孢杆菌（B. subtilis）和大肠杆菌（E. coli），在低于LCST（28°C）和高于LCST（37°C）的条件下，证明了三元纳米杂化物的热响应抗菌功效。结果表明，在28°C时，在亲水性细菌（枯草芽孢杆菌）中观察到了很强的抗菌能力。相反，由于AgNP/NSP-PNiPAAm的表面能调节，在37°C时，在疏水性细菌（大肠杆菌）中发现了优异的抗菌能力。含银三元纳米杂化物的定制使得新型抗菌纳米材料能够通过改变温度选择性地影响细菌表面。
