Multifunctional Carbon Nanodots for Antibacterial Enhancement, pH Change, and Poisonous Tin(IV) Specifical Detection

In recent years, antibiotic-based carbon nanodots have been extensively developed and studied, because of their excellent synergistic fluorescence and antibacterial properties. These antibacterial carbon nanodots have also been developed with various new applications, such as heavy iron detection, pH sensitivity, temperature response, and bacterial count detection in various environments. In this article, using vancomycin hydrochloride as the only precursor, vancomycin hydrochloride carbon nanodots were rapidly synthesized by a one-step microwave method. The diameter of the vancomycin hydrochloride carbon nanodots was concentrated at 0.899 ± 0.40 nm with a uniform size and excitation-dependent fluorescence. Vancomycin hydrochloride carbon nanodots showed better antibacterial activity than the original vancomycin hydrochloride with low biological toxicity and good stability. In the pH range of approximately 7-13, there was a good linear relationship between the fluorescence intensity of the carbon nanodots and the pH value (R² = 0.98516). Moreover, vancomycin hydrochloride carbon nanodots could quickly and specifically detect poisonous Sn⁴⁺ through changes in their fluorescence intensity, with a detection limit of approximately 5.2 μM. Multifunctional vancomycin hydrochloride carbon nanodots have good application prospects in the fields of antibacterial, toxic Sn⁴⁺ detection, and pH-sensitive aspects.