Maintaining creatinine at high and low level is critical because it causes so many problems such as diabetic nephropathy, muscular dystrophy, renal failure, and urinary tract blocking. In this study, a high-performance near-infrared fluorescent Ag2S-functionalized-COOH quantum dots (QDs) capped with molecularly imprinted polymer (MIP) was developed (Ag2S@MIP) and used as a facile selective and sensitive detector for creatinine. Ethylene glycol dimethacrylate as cross-linker and creatinine as template molecules was used to prepare Ag2S@MIP fluorescent nanoparticles (∼42 nm) of the core-shell structure and by grafting methacrylic acid monomer on the surface of methacrylate-functionalized Ag2S QDs using suspension polymerization. The Ag2S@MIP nanoparticles were prepared and characterized by FESEM, FT-IR, DLS, TGA, XRD, and EDS. The Ag2S@MIP nanoparticles displayed a fluorescence emission band at ∼834 nm and quenched strongly upon the addition of creatinine. The adsorption of creatinine at various experimental conditions such as fluorescent emission, selectivity, adsorption/desorption processes, and reusability of Ag2S@MIP was measured. The outstanding adsorption capacity (∼492 mg/g) and the selectivity factor of Ag2S@MIP give a promising sensor for the detection and determination of creatinine in the human serum.
