ZIF-8 gated dual miRNA-sensing nanoplatform for enzyme-free amplification and precision diagnosis of metabolic dysfunction-associated steatohepatitis.

Ultrasensitive and reliable imaging of miRNAs in living cells facilitates advanced understanding of diseases and pathological progression. However, synchronous detection of multicomponent miRNAs remains challenging due to obstacles in the efficient co-delivery of probes and their inherently low abundance. Herein, we present a versatile Hairpins@ZIF-8 nanoplatform by integrating ZIF-8 with three hairpins for dual miRNA sensing. This system enables synchronous cellular transfection of nucleic acid probes, acid-responsive degradation preventing nonspecific activation during endocytosis-dependent delivery, and probe stabilization with degradation-released metal ions serving as cofactors for enzyme-free signal amplification. The ZIF-8 gated dual miRNA-sensing nanoplatform demonstrated high sensitivity in vitro, synchronously detecting miRNA-122 and miRNA-21 with detection limits of 52 pM and 48 pM, respectively. Benefiting from its superior performance, it was applied to metabolic dysfunction-associated steatohepatitis (MASH) models and visualized time-dependent dual-miRNA expression changes in sodium palmitate-induced L02 cells, showing promise for early MASH diagnosis and pathological elucidation. Notably, we provide the first visual evidence demonstrating that miRNA-122 regulates miRNA-21 expression. This strategy provides both a tool for deciphering MASH progression and a platform for advancing miRNA diagnostics and therapeutics.