Cryo-Engineered DNA Cryogels with Interconnected Macroporous Architectures for Enhanced Mass Transfer and Ultrasensitive cTnI Detection via an Integrated Microfluidic Platform

Cardiac Troponin I (cTnI) is a definitive clinical biomarker for the diagnosis of acute myocardial infarction (AMI). Thus, its rapid and precise quantification is of paramount significance for clinical intervention. DNA hydrogels represent a premier choice for constructing rapid detection platforms due to their excellent target responsiveness. However, the severe mass transfer resistance inherent in the dense nanoscale networks of conventional hydrogels restricts the transport of biological macromolecules and signal probes, thereby limiting detection efficiency and sensitivity. In this study, an intelligent colorimetric sensing platform was developed by coupling a CRISPR-Cas12a system with a cryo-engineered DNA cryogel, integrated with a microfluidic chip and machine learning algorithms. Compared with conventional DNA hydrogels, the cryo-engineered DNA cryogel features an interconnected macroporous architecture that significantly reduces mass transfer resistance, thereby enabling bidirectional transport enhancement of CRISPR-nanozymes and accelerating signal response. Under optimized conditions, coupled with a microfluidic system and machine learning, the sensing platform exhibited a robust linear relationship within the range of 0.003-10.00 ng mL-1, with an ultralow detection limit of 0.011 pg mL-1. This strategy pioneers a novel pathway for rapid home screening of cTnI, establishing a critical paradigm for high-performance sensing platforms through material structural modulation and multidisciplinary integration.