Successfully interfacing enzymes and biomachineries with polymers affords ondemand modification and/or programmable plastic degradation during manufacture, utilization, and disposal, but requires controlled biocatalysis in solid matrices with macromolecular substrates. [1][2][3][4][5][6][7] Embedded enzyme microparticles have sped up polyester degradation, but compromise host properties and unintentionally accelerate microplastics formation with partial polymer degradation. 6,8,9 Here, by nanoscopically dispersing enzymes with deep active sites, semi-crystalline polyesters can be degraded primarily via chain-end mediated processive depolymerization with programmable latency and material integrity, akin to polyadenylationinduced mRNA decay. 10 It is also feasible to realize the processivity with enzymes having surface-exposed active sites by engineering enzyme/protectant/polymer complexes.Polycaprolactone and poly(lactic acid) containing less than 2 wt.% enzymes are depolymerized in days with up to 98% polymer-to-small molecule conversion in standard soil composts or household tap water, completely eliminating current needs to separate and landfill their products in compost facilities. Furthermore, oxidases embedded in polyolefins retain activities. However, the hydrocarbon polymers do not closely associate with enzymes like their polyester counterparts and the reactive radicals generated cannot chemically modify the macromolecular host. The studies described here provide molecular guidance toward the enzyme/polymer pairing and enzyme protectants' selection to modulate substrate selectivity and optimize biocatalytic pathways. They also highlight the need for in-depth research in solid-state enzymology, especially in multi-step enzymatic cascades, to tackle chemically dormant substrates without creating secondary environmental contamination and/or biosafety concerns.

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Electronic waste carries energetic costs and an environmental burden rivaling that of plastic waste due to the rarity and toxicity of the heavy‐metal components. Recyclable conductive composites are introduced for printed circuits formulated with polycaprolactone (PCL), conductive fillers, and enzyme/protectant nanoclusters. Circuits can be printed with flexibility (breaking strain ≈80%) and conductivity (≈2.1 × 104 S m−1). These composites are degraded at the end of life by immersion in warm water with programmable latency. Approximately 94% of the functional fillers can be recycled and reused with similar device performance. The printed circuits remain functional and degradable after shelf storage for at least 7 months at room temperature and one month of continuous operation under electrical voltage. The present studies provide composite design toward recyclable and easily disposable printed electronics for applications such as wearable electronics, biosensors, and soft robotics.

Alkylative ring-opening reactions of stable 2-substituted N-methylaziridinium ions proceeded with various alkyl- or arylmagnesium bromides in the presence of CuI to yield synthetically valuable and optically pure alkylated acyclic amines in a completely regio- and stereoselective manner. This was applied to a formal synthesis of the cytotoxic natural product tyroscherin.