We describe a novel method to prepare a liquid-solid hybrid catalyst via interfacial growth of a porous silica crust around Pickering emulsion droplets, which allowed us to overcome the current limitations of both homogeneous and heterogeneous catalysts. The inner micron-scaled liquid (for example, ionic liquids) pool of the resultant catalyst can host free homogeneous molecular catalysts or enzymes to create a true homogeneous catalysis environment. The porous silica crust of the hybrid catalyst has excellent stability, which makes it amenable to packing directly in fixed-bed reactors for continuous flow catalysis. As a proof of concept, the enzymatic kinetic resolution of racemic alcohols, Cr III (salen) complex-catalyzed asymmetric ring opening of epoxides and Pd-catalyzed Tsuji-Trost allylic substitution reactions were used to verify the generality and versatility of our strategy for bridging homogeneous and heterogeneous catalysis. The hybrid catalyst-based continuous flow system exhibited a 1.6~16-fold enhancement in activity relative to homogeneous counterparts even at more than 1500 h, and the afforded enantioselectivities were completely equal to those obtained in the homogeneous counterpart systems. Interestingly, the catalytic efficiency can be tuned through rational engineering of the porous crust and the dimensions of the liquid pool, resulting in features of an innovatively designed catalyst. This contribution provides a new method to design efficient catalysts that can bridge the conceptual and technical gaps between homogeneous and heterogeneous catalysis.

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In this manuscript, the fabrication of an amperometric cholesterol biosensor based on silver nanowires (AgNWs) and cholesterol oxidase (ChOx)-graphene oxide (GO)-chitosan (CS) film is reported. The electrochemical behaviour of the ChOx/Ag/GO/CS/ITO biosensor was studied using cyclic 10 voltammetry (CV), which revealed that the developed biosensor possessed high sensitivity(13.628µA mM −1 cm -2 ) and low detection limit (0.427mgdL -1 ). The apparent Michaelis-Menten constant, K M app of this biosensor was very low (2.813mM), originating from the effective immobilization 15 process and the nanopwires structure of the substrate. The biosensor expressed a wide linear range up to 400mgdL -1 in a physiological condition (pH 7.0), making it very promising for the clinical determination of cholesterol.