Protein-Templated Ultrasmall Pt Nanocluster in Adenosine ATP-Responsive MOF Nanoarchitectonics for Ultrasensitive Point-of-Care Detection

Adenosine triphosphate (ATP), a universal biomarker of cellular metabolism, demands rapid and reliable point-of-care detection (POCT), yet conventional colorimetric biosensors suffer from insufficient sensitivity and poor operational stability. Herein, we present a nanobio interface engineering strategy that synergizes nanozyme catalysis with metal-organic framework (MOF) biomimetic mineralization, addressing critical limitations in ATP diagnostics. The Pt nanoclusters (Pt NCs), templated and stabilized by glucose oxidase under ambient conditions, exhibit ultrasmall sizes (2.30 ± 0.52 nm) and suppressed aggregation, resulting in a ca. 4-fold enhancement in oxidase-like activity owing to highly accessible active sites. These Pt NCs nanozymes are orientationally anchored within ATP-cleavable metal-organic framework (MOF) surface layers through biomimetic mineralization, forming a robust ATP-specific nanoprobe. ATP-triggered disassembly of the MOF matrix releases the Pt NCs nanozyme, yielding a colorimetric "turn-on" response by leveraging its intensified oxidase-like catalytic activity. This approach achieves a linear range of 0.2-1000 μM in simulated biological fluids, with an ultralow detection limit of 62 nM, several times to 3 orders of magnitude lower than existing POCT sensors. This work not only establishes a sensitive yet convenient platform for ATP monitoring but also provides new insight into the design of a stimuli-responsive nanozyme-MOF nanoprobe for multiplex biomarker detection.