Gao Peng, Wang Hao, Zou Guifu, Zhang Ke-Qin
National Engineering Laboratory for Modern Silk, College of Textile and Clothing Engineering, Soochow University Suzhou 215123 P. R. China
College of Physics, Optoelectronics and Energy, Collaborative Innovation Center of Suzhou Nano Science and Technology, Soochow University Suzhou 215006 P. R. China.
RSC Adv. 2018 Aug 3;8(49):27805-27810. doi: 10.1039/c8ra04607g. eCollection 2018 Aug 2.
Fluorescent silver nanoclusters (Ag NCs) that are capable of emitting green light have been synthesized using a peptide derived from the C terminal of silk fibroin heavy chain (CSH) a one-pot, green, and facile synthesis method. The emission was also found to be stable at the excitation wavelength and the fluorescence quantum yield of Ag NCs was measured to be 1.1%. Matrix assisted laser desorption ionization time of flight mass spectrometry (MALDI-TOF MS) indicated the presence of a range of Ag species that correspond to Ag1, Ag2, Ag3 and Ag4. Transmission electron microscopic analyses suggested that the formed particles are uniform and well dispersive with an average diameter of 2.5 nm. The Ag NCs were successfully applied to cell imaging in murine preosteoblast MC3T3-E1 cells. Finally, Ag NCs observed by MTT exhibited distinct cytotoxicity at CSH-Ag NCs concentrations of 600 μM. Based on the concept of utilizing a functional peptide from nature, this study demonstrates a novel approach to fabricate aqueous metal nanoclusters for tracking applications in bioimaging.
利用一种源自丝素蛋白重链C端的肽（CSH），通过一锅法绿色简便合成方法制备了能够发出绿光的荧光银纳米簇（Ag NCs）。还发现该发射在激发波长下是稳定的，并且测得Ag NCs的荧光量子产率为1.1%。基质辅助激光解吸电离飞行时间质谱（MALDI-TOF MS）表明存在一系列对应于Ag1、Ag2、Ag3和Ag4的银物种。透射电子显微镜分析表明，形成的颗粒均匀且分散良好，平均直径为2.5纳米。Ag NCs已成功应用于小鼠前成骨细胞MC3T3-E1细胞的细胞成像。最后，通过MTT观察发现，在CSH-Ag NCs浓度为600μM时，Ag NCs表现出明显的细胞毒性。基于利用天然功能肽的概念，本研究展示了一种制备水性金属纳米簇以用于生物成像追踪应用的新方法。
