TY - JOUR
T1 - Mass spectrometric identification of water-soluble gold nanocluster fractions from sequential size-selective precipitation
AU - Yang, Xiupei
AU - Su, Yan
AU - Paau, Man Chin
AU - CHOI, Martin M F
N1 - Copyright:
Copyright 2012 Elsevier B.V., All rights reserved.
PY - 2012/2/7
Y1 - 2012/2/7
N2 - This paper presents a simple and convenient methodology to separate and characterize water-soluble gold nanocluster stabilized with penicillamine ligands (AuNC-SR) in aqueous medium by sequential size-selective precipitation (SSSP) and mass spectrometry (MS). The highly polydisperse crude AuNC-SR product with an average core diameter of 2.1 nm was initially synthesized by a one-phase solution method. AuNCs were then precipitated and separated successively from larger to smaller ones by progressively increasing the concentration of acetone in the aqueous AuNCs solution. The SSSP fractions were analyzed by UV-vis spectroscopy, matrix-assisted laser desorption/ionization time-of-flight-MS, and thermogravimetric analysis (TGA). The MS and TGA data confirmed that the fractions precipitated from 36, 54, 72, and 90% v/v acetone (F 36%, F 54%, F 72%, and F 90%) comprised families of close core size AuNCs with average molecular formulas of Au 38(SR) 18, Au 28(SR) 15, Au 18(SR) 12, and Au 11(SR) 8, respectively. In addition, F 36%, F 54%, F 72%, and F 90% contained also the typical magic-sized gold nanoparticles of Au 38, Au 25, Au 18, and Au 11, respectively, together with some other AuNCs. This study shed light on the potential use of SSSP for simple and large-scale preliminary separation of polydisperse water-soluble AuNCs into different fractions with a relatively narrower size distribution.
AB - This paper presents a simple and convenient methodology to separate and characterize water-soluble gold nanocluster stabilized with penicillamine ligands (AuNC-SR) in aqueous medium by sequential size-selective precipitation (SSSP) and mass spectrometry (MS). The highly polydisperse crude AuNC-SR product with an average core diameter of 2.1 nm was initially synthesized by a one-phase solution method. AuNCs were then precipitated and separated successively from larger to smaller ones by progressively increasing the concentration of acetone in the aqueous AuNCs solution. The SSSP fractions were analyzed by UV-vis spectroscopy, matrix-assisted laser desorption/ionization time-of-flight-MS, and thermogravimetric analysis (TGA). The MS and TGA data confirmed that the fractions precipitated from 36, 54, 72, and 90% v/v acetone (F 36%, F 54%, F 72%, and F 90%) comprised families of close core size AuNCs with average molecular formulas of Au 38(SR) 18, Au 28(SR) 15, Au 18(SR) 12, and Au 11(SR) 8, respectively. In addition, F 36%, F 54%, F 72%, and F 90% contained also the typical magic-sized gold nanoparticles of Au 38, Au 25, Au 18, and Au 11, respectively, together with some other AuNCs. This study shed light on the potential use of SSSP for simple and large-scale preliminary separation of polydisperse water-soluble AuNCs into different fractions with a relatively narrower size distribution.
UR - http://www.scopus.com/inward/record.url?scp=84863040254&partnerID=8YFLogxK
U2 - 10.1021/ac2029908
DO - 10.1021/ac2029908
M3 - Article
C2 - 22229882
AN - SCOPUS:84863040254
SN - 0003-2700
VL - 84
SP - 1765
EP - 1771
JO - Analytical Chemistry
JF - Analytical Chemistry
IS - 3
ER -