Cutting‐Edge Technology for Early Intervention in Myocardial Infarction: Portable Fingertips‐Based Immunobiosensor

Abstract Early intervention in acute myocardial infarction can minimize myocardial damage and improve patient survival. Herein, a low‐cost device‐free portable immunobiosensing platform for flexible monitoring of immediate myocardial infarction is reported. CuS‐Pt nanofragments (CuS‐Pt NFs) with high photothermal conversion efficiency (≈26.41%) are synthesized by liquid‐phase polarity‐mediated synthesis. The CuS NFs are loaded in situ with platinum (Pt) nanoreactors using a solvothermal reduction strategy, which is employed to enhance the efficiency of gas production. The resulting CuS‐Pt nanocatalysts are encapsulated within liposomes for signal cascade amplification. Specifically, cardiac troponin I (cTn I), a target biomarker in serum, is captured on pre‐modified microtiter plates and formed into a classical sandwich model. The thermo‐chemically kinetically enhanced CuS‐Pt reactor is released through a one‐step chemical treatment and transferred to a closed gas generator. Under the excitation of a near‐infrared laser emitter, the internal pressure in the gas generator device increases with time and drives the carbon quantum dot solution in the connected hose. The moving distance shows a correlation with the target concentration. This work provides a new implementation for the development of low‐cost, efficient pressure immunosensors without the requirement of a readout device.