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We report a hybrid bioactive system inspired by the biosilicification of diatoms. Monodisperse chloroplast/silica hybrid microspheres with core–shell structure were designed and prepared. Natural fresh chloroplasts, the photosynthetic plant organelle, were surfacely covered with silica shell by mild sol–gel process. The charge of chloroplast surface attracts negatively charged silica particles in the sol generated from subsequent hydrolysis and condensation of the tetraethyl orthosilicate (TEOS), which benefits single-chloroplast encapsulation. SEM images confirm the closed topologies, sizes, and dispersions of hybrid microspheres comparable to those of parent chloroplasts. The elemental analysis using EDX, the particle size distribution analyses using DLS, the thermochemical analyses using TGA measurements and structural characterization using XRD provide evidence for the formation of silica coating. Monitoring declines in the visible light absorption production yields information regarding the declines in the light-harvesting ability of chlorophyll, which confirmed that the silica shell in the present work extends the photochemical vitality of chloroplasts. Results from oxygen production measurements also demonstrate the existence of silica shell confers real protection on the bioactivity of chloroplasts. We envisage that the stand-alone chloroplast encapsulation enables preparation of living-cell-templated microspheres exhibiting capacity for photosynthetic bioreactors, sensors, green coatings, catalysts, more generally opening a window for construction of stable, environment friendly, functional hybrid materials.

We report a new and simple approach to prepare a class of silica-reinforced liposomes with hybrid core-shell nanostructures. The amphiphilic natural structure of lipids was exploited to sequester hydrophobic molecules, namely precursor TEOS and pyrene, in the hydrophobic midplane of liposomal bilayer assemblies in the aqueous phase. Subsequent interfacial hydrolysis of TEOS at the bilayer/water interface and ensuing condensation within the hydrophobic interstices of the lipid bilayer drives silica formation in situ, producing a novel class of silica-lipid hybrid liposils. Structural characterization by scanning- and transmission electron microscopy confirm that the liposils so generated preserve closed topologies and size-monodipersity of the parent lecithin liposomes, and DSC-TGA and XRD measurements provide evidence for the silica coating. Monitoring fluorescence measurements using embedded pyrene yield detailed information on microenvironment changes, which occur during sol-gel process and shed light on the structural evolution during silica formation. We envisage that liposils formed by this simple, new approach, exploiting the hydrophobic core of the lipid bilayer to spatially localize silica-forming precursors enables preparation of stable liposils exhibiting capacity for cargo encapsulation, bicompatibility, and fluorescence monitoring, more generally opening a window for construction of stable, functional hybrid materials.