Citric acid functionalized neomycin carbon dots for cytotoxicity and sensing application

Abstract

Carbon nanomaterials have been applied in various fields. Currently, functionalized carbon nanomaterial with practical tuning and surface functionalization is a tremendously used method. Herein, neomycin-based fluorescent carbon quantum dots were synthesized via hydrothermal method using neomycin and citric acid as a source for selective sensing of Fe sup(3+) metal ions. The as-prepared Neo-CA-CQDs exhibited blue fluorescence, successfully characterized and utilized for sensing various metal ions. The carbon dots showed excellent sensing properties towards Fe sup(3+) metal ions and optical properties were characterized by a fluorescence spectrofluorometer. In addition, pH and biocompatibility studies were investigated for the Neo-CA-CQDs. The average size of the Neo-CA-CQDs was 3-5.7 nm. The quantum yield of the as-prepared Neo-CA-CQDs was 29.3 percent. The limit of detection for Fe sup(3+) sensing was determined to be 6.09 mu M. The sensing of Fe sup(3+) ions was also confirmed through visual detection, as a significant color change of the CQDs was observed. Additionally, a competitive study was conducted to verify the selectivity of the neomycin citric acid-mediated CQDs towards Fe sup(3+). The in vitro cytotoxicity study was performed on a mouse fibroblast cell line (L929) and Human cervical cancer cell line (HeLa).