Cytotoxicity investigation of luminescent nanohybrids based on chitosan and carboxymethyl chitosan conjugated with Bi sub(2)S sub(3) quantum dots for biomedical applications

• Published in: Toxicology research (Cambridge) Vol. 5; no. 4; pp. 1017 - 1028
• Main Authors: Carvalho, Sandhra M, Mansur, Herman S, Ramanery, Fabio P, Mansur, Alexandra AP, Lobato, Zelia IP, Leite, Maria F
• Format: Journal Article
• Language: English
• Published: 01.06.2016
• ISSN: 2045-452X; 2045-4538
• DOI: 10.1039/c6tx00039h

Bioengineered hybrids are emerging as a new class of nanomaterials consisting of a biopolymer and inorganic semiconductors used in biomedical and environmental applications. The aim of the present work was to determine the cytocompatibility of novel water-soluble Bi sub(2)S sub(3) quantum dots (QDs) functionalized with chitosan and O-carboxymethyl chitosan (CMC) as capping ligands using an eco-friendly aqueous process at room temperature. These hybrid nanocomposites were tested for cytocompatibility using a 3-(4,5-dimethylthiazol-2yl) 2,5-diphenyl tetrazolium bromide (MTT) cell proliferation assay with cultured human osteosarcoma cells (SAOS), human embryonic kidney cells (HEK293T cells) and a LIVE/DEAD registered viability-cytotoxicity assay. The results of the in vitroassays demonstrated that the CMC and chitosan-based nanohybrids were not cytotoxic and exhibited suitable cell viability responses. However, despite the "safe by design" approach used in this research, we have proved that the impact of the size, surface charge and biofunctionalization of the nanohybrids on cytotoxicity was cell type-dependent due to complex mechanisms. Thus, these novel bionanocomposites offer promising prospects for potential biomedical and pharmaceutical applications as fluorescent nanoprobes.