標題: Cysteamine-modified diamond nanoparticles applied in cellular imaging and Hg2+ ions detection
作者: Shellaiah, Muthaiah
Simon, Turibius
Venkatesan, Parthiban
Sun, Kien Wen
Ko, Fu-Hsiang
Wu, Shu-Pao
材料科學與工程學系
應用化學系
電子工程學系及電子研究所
Department of Materials Science and Engineering
Department of Applied Chemistry
Department of Electronics Engineering and Institute of Electronics
關鍵字: Diamond nanoparticles;Photoluminescence;Energy transfer;Surface graphitization;Hg2+ induced agglomeration;HeLa cell imaging
公開日期: 28-Jan-2019
摘要: Luminescent cysteamine-modified nanodiamond particles (ND-Cys) have been reported in surface-mediated energy transfer, cell imaging, and metal-ion recognition studies. In normalized photoluminescence (PL) spectral studies, the emission maxima of ND-Cys (at 50 mu g/mL in water) was fixed at 438 nm at 350 nm excitation, producing a blue emission with a quantum yield (Phi) of 0.13. In the dispersion range of 0-800 mu g/mL, ND-Cys exhibited agglomeration-induced energy transfer via red shifting of the PL peak from 438 nm to 451 nm. Analogous to PL studies, Raman interrogations also established the agglomeration and fixed the saturation limit to 500 mu g/mL in water. The low toxicity and biocompatibility of ND-Cys were demonstrated using methyl thiazolyl tetrazolium assay and time-dependent HeLa cell imaging. Subsequently, the Hg2+ selectivity by ND-Cys was revealed by an intense fluorescence peak shift from 440 nm to 463 nm. Fluorescence studies indicated that the detection limit of Hg2+ ions approximated 153 nM. Fourier-transform infrared and X-ray photoelectron spectroscopy (XPS) analyses supported the binding between free thiol (-SH) and amide (-C=O and -NH) groups of ND-Cys to Hg2+. The Hg2+-induced agglomeration and surface graphitization were successfully confirmed by X-ray powder diffraction, XPS, Raman, scanning electron microscopy, transmission electron microscopy, dynamic light scattering, and zeta potential analyses. Effective detection of Hg2+ ions by ND-Cys was validated through HeLa cell imaging at shortened time intervals.
URI: http://dx.doi.org/10.1016/j.apsusc.2018.09.175
http://hdl.handle.net/11536/148431
ISSN: 0169-4332
DOI: 10.1016/j.apsusc.2018.09.175
期刊: APPLIED SURFACE SCIENCE
Volume: 465
起始頁: 340
結束頁: 350
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