Carboxymethyl chitosan functionalization of Bi2S3 quantum dots: Towards eco-friendly fluorescent core-shell nanoprobes.
Designed bioengineered nanocomposites are emerging as a novel class of hybrid materials composed of natural aminopolysaccharides and inorganic semiconductors for biomedical and environmental applications. In this study, it is reported for the first time the synthesis and characterization of water-soluble Bi2S3 quantum dots (QDs) functionalized with O-carboxymethyl chitosan (O-CMC) as capping ligands. UV-vis spectroscopy, transmission electron microscopy, dynamic light scattering, zeta potential, and photoluminescence spectroscopy were used to characterize these nanohybrids. The results proved the hypothesis that O-CMC acted as a pH-dependent multi-functional ligand by altering the mechanisms of nucleation, growth and stabilization of water-soluble colloidal Bi2S3 nanocrystals under acidic, physiological and alkaline conditions, using an eco-friendly aqueous process at room temperature. Moreover, the O-CMC capping ligand and the relative molar ratios of the precursors in solution effectively controlled the diameters of the Bi2S3 QDs, which ranged from 2.8 to 12.8nm, and that exhibited luminescent properties in visible light.
Center of Nanoscience, Nanotechnology and Innovation-CeNano2I, Department of Metallurgical and Materials Engineering, Federal University of Minas Gerais, Brazil.
Alexandra A P
AA
Mansur
Center of Nanoscience, Nanotechnology and Innovation-CeNano2I, Department of Metallurgical and Materials Engineering, Federal University of Minas Gerais, Brazil.
Fábio P
FP
Ramanery
Department of Chemistry, Federal University of Minas Gerais, Brazil.
Luiz C
LC
Oliveira
Center of Nanoscience, Nanotechnology and Innovation-CeNano2I, Department of Metallurgical and Materials Engineering, Federal University of Minas Gerais, Brazil. Electronic address: hmansur@demet.ufmg.br.
Herman S
HS
Mansur
D001729:Bismuth / Q000737:chemistry*; D048271:Chitosan / Q000031:analogs & derivatives* / Q000737:chemistry; D000067493:Dynamic Light Scattering; D046529:Microscopy, Electron, Transmission; D053758:Nanoparticles; D045663:Quantum Dots / Q000737:chemistry*; D013057:Spectrum Analysis; D013440:Sulfides / Q000737:chemistry*
D013440:Sulfides; C514968:carboxymethyl-chitosan; D048271:Chitosan; D001729:Bismuth; C049897:bismuth sulfide
Biopolymer; Carboxymethyl chitosan; Chitosan; Hybrid; Nanocomposite; Polysaccharides