Highly specific colorimetric detection of sarcosine using surface molecular imprinted Zn/Ce-ZIF.

[Display omitted] • Developed molecularly imprinted nanozymes with exceptional selectivity for the detection of Sar. • Achieved colorimetric sensing of Sar completely free from bioenzymes. • Theoretical calculations provide empirical evidence to support ligand screening. • Rapid adsorption of Sar onto the Zn/Ce-ZIF@MIP surface inhibits its enzymatic activity. Despite significant progress in nanozyme research and the advancement of analytical techniques, the inherent lack of specificity for target analytes often limits their utility in analysis. Integrating specific recognition capabilities into inorganic nanomaterials, independent of biological catalysts or adaptors, represents a crucial breakthrough in the field. Detecting Sarcosine (Sar) in human urine has recently emerged as a non-invasive biomarker for prostate cancer (PCa), presenting a valuable diagnostic tool. This study introduces a novel method for embedding molecular imprinting sites directly onto the surface of a Zn/Ce-based zeolitic imidazolate framework (Zn/Ce-ZIF) nanozyme, facilitating the development of a highly specific colorimetric assay for precise Sar measurement. By utilizing the lanthanide metal cerium as the catalytic element and ZIF-8 as the structural scaffold, we synthesized spherical Zn/Ce-ZIF nanozymes with exceptional oxidase-like catalytic efficiency. The efficiency of molecular imprinting experiments and the ability of molecularly imprinted polymers (MIPs) to identify target molecules were significantly enhanced by using theortical calculations to screen suitable functional monomers. The molecularly imprinted nanozyme (Zn/Ce-ZIF@MIP) initiates a colorimetric oxidation reaction of 3,3′,5,5′-tetramethylbenzidine (TMB), wherein the presence of Sar facilitates selective recognition and capture by the MIP shell, modulating the colorimetric response by hindering TMB's access to the catalytic site. An intelligent color extraction detection device has been developed for the rapid perception of Sar. This colorimetric sensing platform has been validated through the detection of Sar in simulated urine samples. Overall, the application of surface molecular imprinting enhances the functionality of nanozymes in analytical fields. [ABSTRACT FROM AUTHOR]