State Key Laboratory of Chemical Resource Engineering, College of Materials Science and Engineering, Beijing University of Chemical Technology, Beijing, 100029, PR China.
Macromol Rapid Commun. 2013 Aug;34(16):1319-24. doi: 10.1002/marc.201300355. Epub 2013 Jul 15.
This communication reports the first gold nanoparticles (NPs) chirally functionalized with optically active helical substituted polyacetylene (the resulting hybrid particles are defined as Au@PPA NPs). The novel nanoparticles consist of gold as core and optically active helical poly(N-propargylamide) as shell and show considerable optical activity derived from helical poly(N-propargylamide) chains with predominantly one-handed screw sense. The Au@PPA NPs are prepared by a three-step approach: i) a thiol-containing N-propargylamide monomer [Mth , HC≡CCH2 NHCO(CH2 )10 SH] is synthesized and characterized with FTIR and(1) HNMR spectroscopy and elemental analysis; ii) a copolymer (poly(Mth -co-Mch )) was prepared by starting from monomer Mth and another chiral N-propargylamide monomer (Mch ); poly(Mth -co-Mch ) formed helical conformations and showed optical activities; and, iii) Au@PPA NPs are prepared from hydrogen tetrachloroaurate (III) and poly(Mth -co-Mch ) through a one-spot procedure by using LiBH4 as reducing agent. The as-obtained hybrid nanoparticles are characterized by FTIR spectroscopy, TEM, UV-vis absorption and circular dichroism (CD) techniques. UV-vis and CD measurements demonstrated the remarkable optical activity of the Au@PPA NPs. More interestingly, the Au@PPA NPs show much stronger UV-vis and CD sigals when compared to the corresponding orginal helical copolymer, poly(Mth -co-Mch ). The chiral hybrid nanoparticles demonstrate different absorption toward (R)-(+)- and (S)-(-)-1-phenylethylamines, preferentially adsorbing the (S)-isomer.
本通讯报道了首例手性功能化金纳米粒子（Au@PPA NPs）。这些新型纳米粒子由金核和手性螺旋聚（N-丙炔酰胺）壳组成，具有显著的圆二色性，来源于主要具有单一手性螺旋的螺旋聚（N-丙炔酰胺）链。Au@PPA NPs 是通过三步法制备的：i）合成了含有巯基的 N-丙炔酰胺单体 [Mth, HC≡CCH2 NHCO(CH2 )10 SH]，并通过 FTIR 和（1）HNMR 光谱和元素分析进行了表征；ii）从单体 Mth 和另一个手性 N-丙炔酰胺单体（Mch）出发制备了共聚物（poly(Mth-co-Mch)），poly(Mth-co-Mch) 形成了螺旋构象并表现出光学活性；iii）通过 LiBH4 作为还原剂，从四氯金酸（III）和 poly(Mth-co-Mch) 一步制备 Au@PPA NPs。通过 FTIR 光谱、TEM、UV-vis 吸收和圆二色性（CD）技术对所得到的混合纳米粒子进行了表征。UV-vis 和 CD 测量证明了 Au@PPA NPs 的显著光学活性。更有趣的是，与相应的原始螺旋共聚物 poly(Mth-co-Mch) 相比，Au@PPA NPs 具有更强的 UV-vis 和 CD 信号。手性混合纳米粒子对（R）-（+）-和（S）-（-）-1-苯乙胺表现出不同的吸附性，优先吸附（S）异构体。
