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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, CrIII(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 over 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.

A highly sensitive and selective cholesterol biosensor is successfully fabricated in this work. Due to excellent conductivity and catalytic activity, silver nanowires (AgNWs) and zinc oxide (ZnO) are modified on an indium tin oxide (ITO) electrode with graphene oxide (GO) and chitosan (CS) to construct the novel amperometric biosensor. The composite of AgNW–ZnO successfully enhanced electron communication, and the electrochemical performances of the ChOx/ZnO/Ag/GO–CS/ITO electrode were investigated viascanning electron microscopy (SEM), cyclic voltammetry (CV) and impedance measurements. The linear response to cholesterol in the range of the fabricated biosensor is 0.25–400 mg dL−1(6.5 μM to 10 mM) with a sensitivity of 9.2 μA μM−1cm−2. Moreover, the limit of detection (LOD) is 0.287 μM (S/N = 3), and the Michaelis–Menten constant is calculated to be about 0.295 μM in 0.1 M phosphate buffer solution (pH 7).

The present study aims to construct a biosensor to detect cholesterol by ChOx/HRP/Au/APTES/ITO. We tested the electrochemical characterization of this electrochemical sensor electrode using a cyclic voltammetry (CV) technique. Meanwhile, the electron transfer properties of the electrodes after different surface modifications were characterized by electrochemical impedance spectroscopy (EIS). This study demonstrated AuNPs as efficient electron transfer mediators for enzymes based on electrochemical cholesterol biosensors. The calibration linear relationship range of cholesterol was 0.5–450 mg dL−1with a sensitivity of 7.5 μA mg−1dL−1cm−2. The excellent performances of the developed biosensor indicated that it can act as a promising candidate for the electrochemical detection of cholesterol.

In this study, 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 voltammetry (CV), which revealed that the developed biosensor possessed high sensitivity (13.628 μA mM−1cm−2) and a low detection limit (0.427 mg dL−1). The apparent Michaelis–Menten constant, KappM, of this biosensor was very low (2.813 mM), originating from the effective immobilization process and the nanowires structure of the substrate. The biosensor expressed a wide linear range up to 400 mg dL−1in physiological conditions (pH 7.0), making it very promising for the clinical determination of cholesterol.

PPP2R2B, a protein widely expressed in neurons throughout the brain, regulates the protein phosphatase 2A PP2A activity for the microtubuleassociated protein tau and other substrates. Altered PP2A activity has been implicated in spinocerebellar ataxia 12, Alzheimers disease AD, and other tauopathies. Through a casecontrol study and a reporter assay, we investigated the association of PPP2R2BCAG repeat polymorphism with Taiwanese AD, essential tremor ET, Parkinsons disease PD, and schizophrenia and clarified the functional implication of this polymorphism. The distribution of the alleles was not significantly different between patients and controls, with 68.6–76.1 alleles at lengths of 10, 13, and 16 triplets. No expanded alleles were detected in either group. However, the frequency of the individuals carrying the short 5, 6, and 7triplet alleles was notably higher in patients with AD 5180 2.8, Fishers exact test, P  0.003; including 2 homozygotes and ET 4132 3.0, Fishers exact test, P < 0.001 than in the controls 1625 0.2. The PPP2R2Btranscriptional activity was significantly lower in the luciferase reporter constructs containing the CAG5–7allele than in those containing the common 10, 13, and 16triplet alleles in both neuroblastoma and embryonic kidney cells. Therefore, our preliminary results suggest that the PPP2R2Bgene CAG repeat polymorphism may be functional and may, in part, play a role in conferring susceptibility to AD and ET in Taiwan. © 2008 WileyLiss, Inc.