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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., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Background: Early prostatic cancer (PCa) diagnosis significantly improves the chances of successful treatment and enhances patient survival rates. Traditional enzyme cascade-based early cancer detection methods offer efficiency and signal amplification but are limited by cost, complexity, and enzyme dependency, affecting stability and practicality. Meanwhile, sarcosine (Sar) is commonly considered a biomarker for PCa development. It is essential to develop a Sar detection method based on cascade reactions, which should be efficient, low skill requirement, and suitable for on-site testing., Results: To address this, our study introduces the synthesis of organic-inorganic self-assembled nanoflowers to optimize existing detection methods. The Sar oxidase (SOX)-inorganic hybrid nanoflowers (Cu 3 (PO 4 ) 2 :Ce@SOX) possess inherent fluorescent properties and excellent peroxidase activity, coupled with efficient enzyme loading. Based on this, we have developed a dual-mode multi-enzyme cascade nanoplatform combining fluorescence and colorimetric methods for the detection of Sar. The encapsulation yield of Cu 3 (PO 4 ) 2 :Ce@SOX reaches 84.5 %, exhibiting a remarkable enhancement in catalytic activity by 1.26-1.29 fold compared to free SOX. The present study employing a dual-signal mechanism encompasses 'turn-off' fluorescence signals ranging from 0.5 μM to 60 μM, with a detection limit of 0.226 μM, and 'turn-on' colorimetric signals ranging from 0.18 μM to 60 μM, with a detection limit of 0.120 μM., Significance: Furthermore, our study developed an intelligent smartphone sensor system utilizing cotton swabs for real-time analysis of Sar without additional instruments. The nano-platform exhibits exceptional repeatability and stability, rendering it well-suited for detecting Sar in authentic human urine samples. This innovation allows for immediate analysis, offering valuable insights for portable and efficient biosensors applicable to Sar and other analytes., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)