Nanoengineered Carbon Dots for Enhanced Antibacterial Response and Sensitive Bacterial Sensing

The relevance of carbon dots (CDs) in a variety of application areas has drawn a lot of interest. The CDs for enhanced antibacterial activity and the sensitive identification of pathogenic bacteria are described. The CDs and N-CDs were produced using a microwave, which provided a quick, one-pot, and economical method. CDs and N-CDs showed a high stability for up to 3 months, with an average diameter of 5.761 ± 0.263 nm and 4.226 ± 0.210 nm, respectively. The higher inhibition zone and decreased bacterial growth demonstrated the enhanced antibacterial properties of N-CDs compared to CDs. A regression calibration curve was set up for quantitatively measuring Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli) using CDs and N-CDs resulting in a high square of correlation coefficient with r² > 0.99. Electrostatic interaction explains the tenable mechanism. CDs and N-CDs were tested to assess their ability to probe bacteria in orange juice. The analytical performance was validated using recovery tests with an acceptable range and relative standard deviation resulting in a good value of less than 4%. Nanosensor carried out in orange juice confirmed the viability of this sensing strategy and its potential to expand the detection of S. aureus and E. coli bacteria.