Synthesis and Stability of Fluorescent Gold Nanoparticles by Sodium Borohydride in the Presence of Mono-6-deoxy-6-pyridinium-
pubs.acs.org/images/gifchars/beta2.gif" border="0" align="
详细信息 查看全文
- 作者：Keith B. Male ; Jianjun Li ; Ching Chi Bun ; Siu-Choon Ng ; John H. T. Luong
- 刊名：Journal of Physical Chemistry C
- 出版年：2008
- 出版时间：January 17, 2008
- 年：2008
- 卷：112
- 期：2
- 页码：443 - 451
- 全文大小：517K
- 年卷期：v.112,no.2(January 17, 2008)
- ISSN：1932-7455
文摘
Gold nanoparticles in the range of 5-6 nm were synthesized by the reduction of gold(III) chloride trihydrateby sodium borohydride (SBH) in the presence of newly synthesized mono-6-deoxy-6-pyridinium-
gifchars/beta2.gif" BORDER=0 ALIGN="middle">-cyclodextrinchloride (p-gifchars/beta2.gif" BORDER=0 ALIGN="middle">CD). NMR, mass spectroscopy, and UV-vis spectroscopy illustrated that SBH wouldsimultaneously reduce both p-gifchars/beta2.gif" BORDER=0 ALIGN="middle">CD and gold salt even though the reduction of the latter occurs more rapidly.Resulting gold nanoparticles were capable of oxidizing the reduced p-gifchars/beta2.gif" BORDER=0 ALIGN="middle">CD, leading to the formation of thep-gifchars/beta2.gif" BORDER=0 ALIGN="middle">CD-gold complex via hydrogen bonding and ionic interaction. Gold nanoparticles were synthesized froma much higher concentration (1.0 mM vs 0.25 mM in the absence of p-gifchars/beta2.gif" BORDER=0 ALIGN="middle">CD) of gold salt and were notsusceptible to aggregation by NaCl, phosphate (pH 4-10), acetate, citrate, and borate. The p-gifchars/beta2.gif" BORDER=0 ALIGN="middle">CD-goldnanoparticle assembly displayed intensified fluorescence with emission at 498 nm when excited at 470 nm,a phenomenon known as metal-enhanced fluorescence. The gold nanoparticles acted as electron acceptorsand controlled the pathways of the excited-state deactivation. Surface binding of the pyridinium moiety ofp-gifchars/beta2.gif" BORDER=0 ALIGN="middle">CD to gold nanoparticles suppressed the intramolecular photoinduced electron transfer from the lone pairof the nitrogen atom to the aromatic ring and thereby increased the efficiency of radiative deactivation, leadingto a fluorescence enhancement. The p-gifchars/beta2.gif" BORDER=0 ALIGN="middle">CD-gold nanoparticle system could be exploited for variousfluorescence chemosensing and biosensing schemes, especially for applications demanding long observationtimes without photobleaching.
gifchars/beta2.gif" BORDER=0 ALIGN="middle">-cyclodextrinchloride (p-gifchars/beta2.gif" BORDER=0 ALIGN="middle">CD). NMR, mass spectroscopy, and UV-vis spectroscopy illustrated that SBH wouldsimultaneously reduce both p-gifchars/beta2.gif" BORDER=0 ALIGN="middle">CD and gold salt even though the reduction of the latter occurs more rapidly.Resulting gold nanoparticles were capable of oxidizing the reduced p-gifchars/beta2.gif" BORDER=0 ALIGN="middle">CD, leading to the formation of thep-gifchars/beta2.gif" BORDER=0 ALIGN="middle">CD-gold complex via hydrogen bonding and ionic interaction. Gold nanoparticles were synthesized froma much higher concentration (1.0 mM vs 0.25 mM in the absence of p-gifchars/beta2.gif" BORDER=0 ALIGN="middle">CD) of gold salt and were notsusceptible to aggregation by NaCl, phosphate (pH 4-10), acetate, citrate, and borate. The p-gifchars/beta2.gif" BORDER=0 ALIGN="middle">CD-goldnanoparticle assembly displayed intensified fluorescence with emission at 498 nm when excited at 470 nm,a phenomenon known as metal-enhanced fluorescence. The gold nanoparticles acted as electron acceptorsand controlled the pathways of the excited-state deactivation. Surface binding of the pyridinium moiety ofp-gifchars/beta2.gif" BORDER=0 ALIGN="middle">CD to gold nanoparticles suppressed the intramolecular photoinduced electron transfer from the lone pairof the nitrogen atom to the aromatic ring and thereby increased the efficiency of radiative deactivation, leadingto a fluorescence enhancement. The p-gifchars/beta2.gif" BORDER=0 ALIGN="middle">CD-gold nanoparticle system could be exploited for variousfluorescence chemosensing and biosensing schemes, especially for applications demanding long observationtimes without photobleaching.