Cysteamine derived N/S co-doped carbon dots for fluorescence imaging of pathogenic bacteria and human buccal epithelial cells

Abstract

Here, we report cysteamine derived nitrogen and sulfur co-doped carbon dots (Cy@CD) for imaging pathogenic bacteria and human buccal epithelial cells. The Cy@CD was synthesized using one-step simple microwave-assisted hydrothermal synthesis with precursors, namely, cysteamine and 50X TAE buffer. The spectroscopic characterization of Cy@CD showed (λex/λem) at 350/434 nm with a decent quantum yield of 13.2%. Cy@CD was deployed in tagging bacterial cells such as E. coli, S. aureus, P. aeruginosa and B. subtilis and human buccal epithelial cells. The multicolour emissive Cy@CD tagged microbial cells were also cross-validated by fluorometry analysis. The fluorescent Cy@CD could be used as an ideal substitute for the harmful synthetic fluorescent stain in cell imaging applications.