caa a22 4500 445879769 CHVBK 20180317145538.0 cr unu---uuuuu 170323e20110201xx s 000 0 eng 10.1007/s00604-010-0480-4 doi (NATIONALLICENCE)springer-10.1007/s00604-010-0480-4 Enhancement of the colorimetric sensitivity of gold nanoparticles with triethanolamine to minimize interparticle repulsion [Elektronische Daten] [Mingyang Ma, Juan Wang, Xingwang Zheng] Cysteine and thioglycolic acid were immobilized on gold nanoparticles via established thiolgold surface chemistry. It is found that calcium ions rapidly induce the aggregation of the functional gold nanoparticles due to the complexation of Ca(II) by immobilized cysteine. It was also found that triethanolamine enhances the effect of calcium ions by decreasing the electrostatic repulsion between the gold nanoparticles. Transmission electron microscopy, electrophoresis, zeta potential measurements and absorptiometry were used to investigate the mechanism. Under the optimum experimental condition, the cysteine/thioglycolate/triethanolamine-modified nanoparticles were highly sensitive (the detection limit being 0.3 μM) and selective towards calcium and magnesium ions, with a linear detection range between 1.0 μM and 14 μM. Based on these findings, a rapid and selective colorimetric method was developed for assaying Ca(II) ions in serum. Figure It was found that triethanolamine could be immobilize on the surface of GNPs by electrostatic adsorption with TGA and neutralize the negative charge of TGA, furthermore reduce the electrostatic repulsion and decrease the interparticle distance between aggregated GNPs (as showed in Scheme 1). These results indicated that TGA and cysteine could be successfully immobilized on the surface of the GNPs to improve the stability of the as-prepared functional GNPs for sensing Ca2+ ion Springer-Verlag, 2010 Gold nanoparticles nationallicence Triethanolamine nationallicence Interparticle repulsion nationallicence Cysteine nationallicence Calcium ions nationallicence Ma Mingyang Key Laboratory of Analytical Chemistry for Life Science of Shaanxi Province, School of Chemistry and Materials Science, Shaanxi Normal University, 710062, Xi 'an, China aut Wang Juan Key Laboratory of Analytical Chemistry for Life Science of Shaanxi Province, School of Chemistry and Materials Science, Shaanxi Normal University, 710062, Xi 'an, China aut Zheng Xingwang Key Laboratory of Analytical Chemistry for Life Science of Shaanxi Province, School of Chemistry and Materials Science, Shaanxi Normal University, 710062, Xi 'an, China aut Microchimica Acta Springer Vienna 172/1-2(2011-02-01), 155-162 0026-3672 172:1-2<155 2011 172 604 https://doi.org/10.1007/s00604-010-0480-4 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s00604-010-0480-4 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Ma Mingyang Key Laboratory of Analytical Chemistry for Life Science of Shaanxi Province, School of Chemistry and Materials Science, Shaanxi Normal University, 710062, Xi 'an, China aut NATIONALLICENCE 700 1- Wang Juan Key Laboratory of Analytical Chemistry for Life Science of Shaanxi Province, School of Chemistry and Materials Science, Shaanxi Normal University, 710062, Xi 'an, China aut NATIONALLICENCE 700 1- Zheng Xingwang Key Laboratory of Analytical Chemistry for Life Science of Shaanxi Province, School of Chemistry and Materials Science, Shaanxi Normal University, 710062, Xi 'an, China aut NATIONALLICENCE 773 0- Microchimica Acta Springer Vienna 172/1-2(2011-02-01), 155-162 0026-3672 172:1-2<155 2011 172 604 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer