Phytochemical synthesis and characterization of bioactive gold and platinum nanoparticles using hypaphorine and their cytotoxic effects towards HCT 116 human colorectal cancer-derived cells

M.Sc. (Nanoscience)Abstract: Globally, colorectal cancer (CRC) is one of the most prevalent cancer and also the leading cause of cancer-related mortality and morbidity. In 2012 alone, the global occurrence of CRC was 1.4 million cases and is expected to increase to more than 2.2 million new cases by 2030. The success rates of the standard treatment modalities are not very high, expensive and are accompanied by very unpleasant side effects. Therefore, effective treatment is advantageous for instant interventions to decrease the mortality and morbidity rates. This study investigated for the first time, phytochemical synthesised gold nanoparticles (AuNPs) and platinum nanoparticles (PtNPs) capped with an indole alkaloid, hypaphorine to act as bioactive cytotoxic nano-agents against cancer cell lines. Among metallic NPs, Gold and platinum NPs exhibit remarkable characteristics that are well known to bring revolution in the biomedical field owing to their remarkable biomedical applications, particularly in cancer therapy. Green synthesis of metallic NPs is of interest due to non-toxic, rapidness as well as eco-friendly benefits over chemical and physical methods. Gold and Pt salts were successfully reduced to their corresponding NPs in the presence of hypaphorine, in a single step; a process that fulfils all criteria of green nanotechnology. Formation of NPs was observed within 5 minutes and characterized using UV-Vis spectroscopy, DLS and TEM, and FTIR. Moreover, MTS and xCELLigence tests were carried out using various concentrations of hypaphorine-capped AuNPs and PtNPs for cytotoxic activity analysis. Phytochemical mediated synthesis of metallic NPs is of interest to biologists and chemists due to non-toxic, rapid as well as eco-friendly benefits over chemical and physical methods. However, fabrication methods for metallic NPs using phytochemicals and studies on their applications in cancer therapy are still sparse. Gold and Pt salts were successfully reduced to their corresponding NPs in the presence of hypaphorine, in a single step; a process that fulfils all criteria of green nanotechnology. Formation of NPs was observed within 5 minutes and characterized using UV-Vis spectroscopy to confirm the synthesis. Morphological characteristics, elemental composition and crystalline nature of the NPs were determined by dynamic light scattering (DLS) and transmission electron microscopy (TEM). Fourier transform infrared (FTIR) analysis was used to identify the functional groups responsible for reducing and capping of NPs. Furthermore, MTS (3-(4, 5-dimethylthiazol-2-yl)-5-(3- carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium) and xCELLigence test were..