Paper Title
Biocompatibility Studies of Self-Assembled Carbon Quantum Dots Synthesized from Palm Date Fruit

Abstract
Quantum dots are well known fluorescent nanoparticles predominantly obtained from semiconductor materials such as cadmium, selenium etc. The major disadvantage of these semiconductor nano particles is the toxicity they possess. Recently, carbon and silicon have been reported to generate intrinsically non-toxic nano particles with a high quantum yield. Its rare properties have led to their wide application in the field of life sciences, optical electronics and many more. The objective of present study was to synthesize biocompatible Carbon quantum dots (CQDs) from an economical green-chemistry approach using Phoenix Dactilyfera (Date Palm). The synthesized CQDs were characterized by analyzing ultraviolet absorption spectra and Transmission electron microscopy. We also attempted to evaluate phytotoxicitity of the nanoparticles on a model plant system Pisum sativum (Pea) at 1000 µg/ml concentration for one week. Phytotoxicity studies revealed nonsignificant difference in percentage germination and length of shoot. Microbial toxicity studies were investigated using two microorganisms E. coli (Gram negative) and B. subtilis (Gram positive) which indicated absence of nanoparticle mediated antimicrobial activity. We also attempted to evaluate the cytotoxicity of CQDs on normal cell lines (WRL 68) by dye exclusion assay which revealed the biocompatibility of CQDs by 80.90% viability even at the highest concentration of 1000 µg/ml. CQDs find potential applications in fields of biomedicine as biomolecule detection, drug carriers, fluorescent tracers, and for controlling the drug release. Due to their qualities of water solubility, photostability and bicompatibility, CQDs also act as good biosensors. The in vitro bioimaging for detection and diagnosis purpose also involves the use of CQDs which are considered to be excellent bioimaging agents due to their stable emission, low toxicity, well dispersability and good biocompatibility. The findings of this research indicate biocompatibility of Date CQDs which when explored more extensively can prove to have numerous applications in various fields.