Enzymatic catalysis in living cells enables the in-situ detection of cellular metabolites in single cells, which could contribute to early diagnosis of diseases. In this study, enzyme is packaged in amorphous metal-organic frameworks (MOFs) via a one-pot co-precipitation process under ambient conditions, exhibiting 5–20 times higher apparent activity than when the enzyme is encapsulated in corresponding crystalline MOFs. Molecular simulation and cryo-electron tomography (Cryo-ET) combined with other techniques demonstrate that the mesopores generated in this disordered and fuzzy structure endow the packaged enzyme with high enzyme activity. The highly active glucose oxidase delivered by the amorphous MOF nanoparticles allows the noninvasive and facile measurement of glucose in single living cells, which can be used to distinguish between cancerous and normal cells.

Smart materials that can respond to multistimuli have been broadly studied. However, the smart materials that can spontaneously answer the ever-changing inner environment of living bodies have not been reported. Here, we report a strategy based on the dynamic chemistry to develop possible self-adapting solid materials that can automatically change shape without external stimuli, as organisms do. The self-adapting property of a chitosan-based self-healing hydrogel has been rediscovered since its dynamic Schiff-base network confers the unique mobility to that solid gel. As a result, the hydrogel can move slowly, like an octopus climbing through a narrow channel, only following the natural forces of surface tension and gravity. The fascinating self-adapting feature enables this hydrogel as an excellent drug carrier for the in vivo wound treatment. In a healing process of the rat-liver laceration, this self-adapting hydrogel demonstrated remarkable superiority over traditional drug delivery methods, suggesting the great potential of this self-adapting hydrogel as a promising new material for biomedical applications. We believe the current research revealed a possible strategy to achieve self-adapting materials and may pave the way toward the further development, study, and application of new-generation smart materials.

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