Utilization of Photoluminescence for the Detection of pH Change in Biological Systems

Abstract

Carbon nanodots are well known in the biomedical industry due to their unique fluorescent characteristics. The photoluminescence and fluorescence quantum yield of nitrogen-based carbon nanodots are excellent. The pH in living cells is very important as a lot of physiological systems are working in our body to keep them within a specific range. As a light change in pH can cause imbalance in cell function and growth. There are many diseases, which are associated with pH change (acidic pH) such as cancer, tuberculosis, and infections. Hence, a sensitive and selective system is needed to monitor the pH in living cells. The composition of carbon nanodots with Polyethylene glycol and showed better chemical stability, high biocompatibility, intense photoluminescence. Therefore, they can be used to evaluate pH detection in living cells. The purpose of this study is to produce nitrogen-based carbon nanodots that are susceptible to photoluminescence properties and high quantum yield. NCDs were synthesized via the Hydrothermal method which is a very facile and cost-effective technique. The synthesised carbon nanodots were evaluated employing FT-IR, UV-Vis, and Fluorescence spectroscopy. Carboxyl functional groups were found to be present on the surface of carbon nanodots, according to FT-IR spectra. Particle size results indicate that the produced carbon nanodots are spherical and have diameters in the range of 255 d.nm. All these experiments confirm that synthesized carbon nanodots possess high photoluminescence, better quantum yield hence forward they can be used for pH detection and other biomedical applications.