Biological matrix-derived carbon quantum dots: Highly selective detection of tetracyclines

As a kind of abundant resource, the development of biomass has been drawn quite more curiosity to the present research community. In this study, a facile, environment friendly, and repeatable one-step hydrothermal synthesis approach of CDs (carbon dots) by using carp roe as raw material was established. The CDs prepared from carp roe did not require any surface modification, besides, it has the properties such as low toxicity, fantastic water solubility and environmental friendliness. The average particle size of the prepared CDs was about 7.60 nm, and the maximum excitation/emission wavelength was 365/443 nm. In order to verify the low toxicity of CDs, two kinds of cells HCT-116 (human colon cancer cell) and MC (mouse cardiomyocytes) were used to investigate the cytotoxicity of CDs. Owing to the inner filter effect (IFE), the fluorescence of CDs can be quenched in the presence of tetracycline antibiotics (TCs), realizing the detection of tetracycline, chlortetracycline, oxytetracycline and other tetracyclines, which has high accuracy and selectivity, providing the foundation of TCs quantification. The value of fluorescence intensity has a linear relationship with the concentration of TCs in the range of 0.1–50 µM, and the detection limit was 41.7 nM. It was suitable to be applied in the detection of tetracycline in river water, serum and milk with good recovery rate (98.6∼104.5%), demonstrating its potential and broad application prospects in detecting TCs in complex matrix.