Dual-functional sensor based on green-emissive carbon dots for erythromycin detection and temperature monitoring

This study reports the synthesis of green-emissive carbon dots ( λ ex  = 399 nm, λ em,max  = 563 nm; G-CDs) using bromothymol blue and dimethylglyoxime as precursors via a solvothermal method. The as-prepared G-CDs were characterized by fluorescence spectrometry, Fourier-transform infrared spectroscopy (FTIR), and X-ray photoelectron spectroscopy (XPS). The synthesized G-CDs exhibited an excitation peak at 399 nm, an emission peak at 563 nm, and a quantum yield of 22.3 %. They demonstrated excellent salt tolerance, photostability, and excitation wavelength-independent emission behavior, indicating single-emission characteristics. Furthermore, the G-CDs showed high selectivity and sensitivity for erythromycin detection and temperature monitoring, yielding satisfactory results in both applications. Thus, G-CDs can serve as a fluorescent probe for simultaneous erythromycin detection and temperature sensing, expanding their potential in environmental fields.