Biocompatible and nuclear penetrating carbon quantum dots for photoresistive bioimaging applications in animal cell lines

Abstract

Organic dyes used today for imaging the diseased cells are toxic and photobleach easily on light exposures. The exclusive spectral properties and the ultra small size of the Carbon Quantum Dots (CQDs) exert assistance in the vast exploration of the cytoplasmic and nuclear regions of human cells. The present work was intended to synthesize carbon quantum dots from Citrus medica juice and its peel by using pyrolysis and hydrothermal methods. The CQDs exhibited blue to green fluorescence at different excitation and emission wavelengths. The fluorescent particles could easily bind to the protein- Bovine Serum Albumen proving its biological membrane binding properties through the quenching studies with increasing concentrations of CQDs. The produced CQDs also exerted a higher antimicrobial effect against both Gram positive and negative bacteria. The biocompatibility of the CQDs was evident through the in vivo toxicity analyses and the nuclear penetration properties. Thus the nanomaterials could be graded superior to the organic stains used conventionally on the fibroblast cells. This study explores the possibilities of synthesizing fluorescent, ultrasmall, biocompatible CQDs that can easily enter the diseased tissues, favors nuclear membrane penetration and assist diagnosis through bio-imaging.