Coupling hCG-based protease sensors with a commercial pregnancy test strip for simple analyses of protease activities.

Proteases play an essential role in many cellular processes, and consequently, abnormalities in their activities are related to various diseases. Methods have been developed to measure the activity of these enzymes, but most involve sophisticated instruments or complicated procedures, which hampers the development of a point-of-care test (POCT). Here, we propose a strategy for developing simple and sensitive methods to analyze protease activity using commercial pregnancy test strips that detect human chorionic gonadotropin (hCG).

Plasmon-Enhanced Surface Photovoltage of ZnO/Ag Nanogratings.

We investigated the surface photovoltage (SPV) behaviors of ZnO/Ag one-dimensional (1D) nanogratings using Kelvin probe force microscopy (KPFM). The grating structure could couple surface plasmon polaritons (SPPs) with photons, giving rise to strong light confinement at the ZnO/Ag interface. The larger field produced more photo-excited carriers and increased the SPV.

Wafer-scale nanoconical frustum array crystalline silicon solar cells: promising candidates for ultrathin device applications.

A high photocurrent of 36.96 mA cm(-2) was achieved for wafer-scaled crystalline Si solar cells with hexagonal nanoconical frustum arrays at the surface. Optical simulations showed that the expected photocurrent of 10 μm thick nanostructured cells could slightly exceed the Lambertian limit.

Polarization-independent light emission enhancement of ZnO/Ag nanograting via surface plasmon polariton excitation and cavity resonance.

In this study, we observed that the photoluminescence (PL) intensity of ZnO/Ag nanogratings was significantly enhanced compared with that of a planar counterpart under illumination of both transverse magnetic (TM) and transverse electric (TE)-mode light. In the TM mode, angle-resolved reflectance spectra exhibited dispersive dips, indicating cavity resonance as well as grating-coupled surface plasmon polariton (SPP) excitation. In the TE mode, cavity resonance only was allowed, and broad dips appeared in the reflectance spectra.

Surface-plasmon-enhanced visible-light emission of ZnO/Ag grating structures.

We investigated the optical properties of ZnO/Ag grating structures fabricated by sputtering and nanoimprint lithography. The grating structures exhibited multiple peak features in broad visible-range photoluminescence (PL) spectra. The PL intensity of the grating was larger than that of a planar thin film by up to two orders of magnitude.