However, low conductivity, diffusion limitations, and large structural deviations have so far been major obstacles for its application in hybrid systems.As a general rule for supercapacitor devices, the electrochemical performance needs to be confi ned to experimental timescales, i.e., on the order of minutes or seconds. [ 1,17 ] Nevertheless, for hybridized Li-HECs, the kinetics imbalance between the two ends impedes the full realization of the high power concept, leading to insuffi cient performance at high currents. In most cases, desirable energy storage (30-90 Wh·kg −1 ) can only be obtained at the expense of the power performance (<3 kW·kg −1 ), [5][6][7]19,22 ] which is far lower than the power performance targets required for new-generation electric vehicles (15 kW·kg −1 ). [ 18 ] Therefore, it will be a major challenge to design electrodes that can overcome the kinetics mismatch as well as achieve rapid electrochemical processes. [ 23 ] With larger external surface areas and shorter ion diffusion paths, various nanoarchitectures show an effective response to rapid redox reactions. [ 3,24 ] In particular, it was demonstrated that nanoscale architectures of less than 10 nm could enable pseudo-capacitance to overcome diffusion limitations for most reactions that occur at/near the surface. [ 25 ] Correspondingly, three-dimensional (3D) architectures with an interconnected carbon matrix render continuous and effi cient electrical conductive networks with electron supplies that guarantee electrochemical reactions at high power. [ 26 ] Here, we present high-power Li-ion hybrid supercapacitors (Li-HSCs) from the prospective of both single electrodes and devices, with two ends concurrently constructed with delicately engineered 3D hierarchical structures to overcome the kinetics discrepancy ( Figure 1 ). A well-designed MnO-graphene composite (MnO@GNS) was devised as the anode with MnO nanocrystals (≈5 nm) homo-dispersed in the 3D architecture, while 3D hierarchical porous N-doped carbon (HNC) was used as the cathode with thin nanosheets forming the overall multi-porous framework. These scaffolds allow fast kinetics with ion diffusion paths narrowed down to ultrafi ne scales, as well as maximum exposure of the exterior surface. Both porous 3D electrodes with 2D ultrathin subunits facilitate high-power charge storage near the surface. The beneficial surface decoration of heteroatoms further improves the pseudo-capacitance performance of HNC, leading to higher capacitance than conventional carbon materials. As expected, the originally-devised hybrid Li-HSCs achieve attractive energy storage of 127 Wh·kg −1 electrodes , and even remains as high as 83.25 Wh·kg −1 at a battery-inaccessible power density of 25 kW·kg −1 with rapid charging within 8 s. Such a coherent design marks a new strategy for rationally fabricating hybrid devices with both high energy and power density by enhancing the exterior surface charge storage.Electrical energy-storage (EES) systems are anticipated to satisfy the increasing demand for large...

A novel nanoparticle-based electrochemical immunoassay of carbohydrate antigen 125 (CA125) as a model was designed to couple with a microfluidic strategy using anti-CA125-functionalized magnetic beads as immunosensing probes. To construct the immunoassay, thionine-horseradish peroxidase conjugation (TH-HRP) was initially doped into nanosilica particles using the reverse micelle method, and then HRP-labeled anti-CA125 antibodies (HRP-anti-CA125) were bound onto the surface of the synthesized nanoparticles, which were used as recognition elements. Different from conventional nanoparticle-based electrochemical immunoassays, the recognition elements of the immunoassay simultaneously contained electron mediator and enzyme labels and simplified the electrochemical measurement process. The sandwich-type immunoassay format was used for the online formation of the immunocomplex in an incubation cell and captured in the detection cell with an external magnet. The electrochemical signals derived from the carried HRP toward the reduction of H(2)O(2) using the doped thionine as electron mediator. Under optimal conditions, the electrochemical immunoassay exhibited a wide working range from 0.1 to 450 U/mL with a detection limit of 0.1 U/mL CA125. The precision, reproducibility, and stability of the immunoassay were acceptable. The assay was evaluated for clinical serum samples, receiving in excellent accordance with results obtained from the standard enzyme-linked immunosorbent assay (ELISA) method. Concluding, the nanoparticle-based assay format provides a promising approach in clinical application and thus represents a versatile detection method.

Methods based on sandwich-type electrochemical enzyme immunoassay protocol have been extensively developed for the detection of biomolecules, but most often exhibit low detection signals and low detection sensitivity, and are unsuitable for routine use. In this study, we initially synthesized specially horseradish peroxidase-encapsulated nanogold hollow microspheres (HRP-GHS), and then the prepared HRP-GHS was conjugated to the secondary carcinoembryonic antibody (HRP-GHS- anti-CEA). Carcinoembryonic antigen (CEA), as a model protein, was monitored by using the electrochemical sandwich-type enzyme immunoassay format. Under optimized conditions, the linear range of the immunoassay by using single HRP-labeled anti-CEA (HRP- anti-CEA) as secondary antibodies is 2.5-120 ng/mL with a detection limit of 1.5 ng/mL CEA, while the assay sensitivity by using HRP-GHS- anti-CEA as secondary antibodies is further increased from 0.01 to 200 ng/mL with a lower detection limit of 1.5 pg/mL CEA. The intra- and interassay reproducibility is acceptable. The CEA concentrations of the clinical serum specimens assayed by the developed immunoassay show consistent results in comparison with those obtained by commercially available enzyme-linked immunosorbent assay. This immunoassay system has many desirable merits including sensitivity, accuracy, and little required instrumentation. Significantly, the new protocol may be quite promising, with potentially broad applications for clinical immunoassays.

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