Synthesis of ultra-small cysteine-capped gold nanoparticles by pH switching of the Au(I)-cysteine polymer

CAPPELLARI, PAULA; DAVID BUCETA; GUSTAVO M. MORALES; CESAR A. BARBERO; MORENO, M. SERGIO; LISANDRO GIOVANETTI; JOSE RAMALLO LOPEZ; FELIX REQUEJO; ALDO CRAIEVICH; GABRIEL A. PLANES

JOURNAL OF COLLOID AND INTERFACE SCIENCE

ACADEMIC PRESS INC ELSEVIER SCIENCE

Lugar: Amsterdam; Año: 2015 p. 17 - 24

0021-9797

We report a synthetic approach for the production of ultra-small (0.6 nm) gold nanoparticles soluble in water with a precise control of the nanoparticle size. Our synthetic approach utilizes a pH-depending Au?cysteine polymer as a quencher for the AuNPs grown. The method extends the synthetic capabilities of nanoparticles with sizes down to 1 nm. In addition to the strict pH control, the existence of free ?SH groups present in the mixture of reaction has been observed as a key requirement for the synthesis of small nanoparticles in mild conditions. UV?Vis, SAXS, XANES, EXAFS and HR-TEM, has been used to determinate the particle size, characterization of the gold precursor and gold?cysteine interaction.