RESUMO
Carbon dots/Prussian blue nanoparticles (CDs/PBNPs) with fluorescence (FL) performance and peroxidase-like activity are synthesized by a simple two-step method. The FL of CDs/PBNPs can be effectively quenched by Fe3+. Fe3+ can accelerate the peroxidase-like activity of CDs/PBNPs. More excitingly, the peroxidase-like activity of CDs/PBNPs could be further enhanced due to the influence of the photothermal effect. Based on the FL property and enhanced peroxidase-like activity, a cascade strategy is proposed for detection of Fe3+ and free cholesterol. CD/PBNPs act as FL probe for detection of Fe3+. The enhanced peroxidase-like activity of CDs/PBNPs can also be used as colorimetric probe for the detection of free cholesterol. The detection ranges of Fe3+ and free cholesterol are 4-128 µM and 2-39 µM, and the corresponding limit of detections are 2.0 µM and 1.63 µM, respectively. The proposed strategy has been verified by the feasibility determination of Fe3+ and free cholesterol, suggesting its potential in the prediction of disease.