A bio‐inspired method is used to render controlled wrinkling surface patterns on supramolecular architectures assembled from polyoxometalate (POM) clusters. It involves a polyamine‐multivalent anion interaction generating positively charged coacervates, which while dictating the assembly of POM into spherical structures further facilitate an interesting surface morphogenesis with wrinkling patterns. This spontaneous surface wrinkling depends on the type of multivalent anion and the pH. As the polyamine‐anion interaction becomes stronger, the wrinkles turn denser with lesser depth, which eventually undergoes post‐buckling to engender a complex surface pattern. Interestingly, the order of influence exerted by different anions on the morphology follows the Hofmeister series. Moreover, the mild synthesis conditions keep the functional POM units dispersed in the sphere with a structural transformability to their lacunary form.

A polyamine-mediated bioinspired strategy to assemble Keggin-type phosphomolybdic acid (PMA) clusters is demonstrated for the fabrication of microcapsule (MC) structures with unique surface textures. It involves supramolecular aggregation of polyamines with multivalent anions, which then allows the assembly of negatively charged PMA into MCs in an aqueous medium under ambient conditions. Resembling the role of polyamines in biosilicification of diatoms, the polyamine-anion interaction is shown to be the key for the assembly process. It not only provides structural stability but also facilitates an interesting transition from a smooth to a wrinkled surface alongside a change in the Keggin form to its lacunary form depending on the pH of the medium. Moreover, the presence of isolated PMA units in the hybrid structure enables them to be active in catalyzing the aerobic oxidation of alkenes under solvent-free conditions with better selectivity and reusability. Hence, the assembly approach represents an effective way for heterogenization of PMA-based materials and is expected to find considerable application in the wider hybrid-cluster field.

A polyamine-mediated bioinspired strategy to assemble polyoxometalate (POM) [phosphotungstic acid (PTA)/ phosphomolybdic acid (PMA)] nanoclusters and glucose oxidase (GOx) generating microsphere structures under very mild reaction conditions is demonstrated. The noncovalent interactions between multivalent anions (citrate ions) and polyamine chains [poly-(allylaminehydrochloride), PAH] are key to the assembly process, which results in positively charged coacervates, allowing the assembly of GOx and POM nanoclusters into microsphere structures. As observed in the process, in addition to having an impact on the size, composition, and textural properties of the spheres, the pH of the reaction medium has a pivotal role in safeguarding the enzyme. The enzyme assay shows that the activity of GOx is totally preserved during the assembly process, and the enzyme loading is slightly improved with the increase in the pH of the medium. In contrast, a physical mixture of GOx and POM leads to the inactivation of the enzyme retaining only ∼50% GOx activity. The peroxidase-like activity of PTA nanoclusters assembled in enzyme-nanozyme microspheres, as indicated by the maximal velocity (V max ) and catalytic constant (k cat ) values, is improved by 3-to5-fold with the increase in the pH, which in turn is attributed to the smaller size of the microspheres, facilitating better diffusion of reactants, intermediates, and products. Importantly, the confinement and proximity of GOx and POM in the microspheres not only play a crucial role in defining the peroxidase-like activity of POM but also endow high selectivity (by virtue of GOx) in detecting glucose at physiological pH conditions. Thus, the microsphere assembly, while enabling effective heterogenization of the POM as a nanozyme, simultaneously addresses the issues related to high cost and instability associated with natural peroxidases.