In-vitro cellular interaction of quantum dots and silicone surfaces

Abstract

The main hypothesis on which this study has been based is that the surface modification of nano-particles of different size (Quantum Dots) and varying nano-surfaces roughness (Silicones of nanosurface roughness) can make them highly biocompatible in various applications of biology and medicine. In this work, attempts were made to investigate if the surface modification of nano-particles by gelatination of different size (Quantum Dots) makes them more biocompatible by reducing the toxicity on the cells and increasing the nano-surface roughness (Silicones of nanosurface roughness ranging from ~88 nm to ~650 nm) makes them more biocompatible by reducing the fibroblast growth of the cells in vitro. To address these questions, the nano-particles [CdTe Quantum dots of thioglycolic acid (TGA) capped gelatinated and non-gelatinated] and nano-surfaces (Silicones of nanosurface roughness) were characterised and then three different types of cells were used to check the biocompatibility in in vitro cell lines. At first, the Quantum Dots (QDs) were co-incubated with undifferentiated Pheochromocytoma12 (PC12) cells and investigated the cellular interaction, uptake and resultant toxic influence of the QD cell interplay was explored as the QD concentrations were varied over extended (up to 72 hours) co-incubation periods. Following this, QDs have been co-incubated with differentiated pheochromocytoma 12 (PC12) cells and the apoptotic process involved in the cell death machinery and also the intrinsic behaviour of QDs upon uptake by the cells have been analysed to extended (up to 17 days) co-incubation periods. In the same experiment, differentiated PC12 cells were also exposed to QDs after the neurites were grown for 10 days. Subsequently QDs were co-incubated with Human Pulmonary Microvascular Endothelial (HPMEC-ST1.6R) cells and analysed their cytotoxicity, differentially expressed genes and also their pathways involved to extended (up to 72 hours) co-incubation periods. Finally, the nano-surface roughnesses of silicone elastomer samples with rms surface roughnesses varying from ~88 nm to ~650 nm were co-incubated with NIH-3T3 fibroblast cells and analysed the total amount of DNA to extended (up to 24 hours) co-incubation periods. In conclusion, it was shown here that the surface modification of nano-particles (Quantum Dots) and nano-surfaces (Silicones of nanosurface roughness) were more biocompatible in vitro.