A new electrophilic sulfoximidation of thiols has been developed. Using sodium hydride as a base, the treatment of sulfoximidoyl-containing hypervalent iodine(III) reagents with thiols affords the corresponding N-sulfenylsulfoximines (N-thiosulfoximines) in good to excellent yields. A plausible mechanism is proposed.

Cylindrical vector beams with polarization singularities, transmission stability and turbulence resilient, are orthogonally structured light beams providing new degrees of freedom for multiplexing optical communications. The demultiplexing of the CVBs with high efficiency and low crosstalk is of vital importance for the practical applications. Here, we propose a lens-less CVB sorting approach with a set of dielectric metasurface devices. The metasurface is composed of elliptical silicon nanopillars, which are capable of vector field steering. By performing mode transformations on both left-handed and right-handed polarization components of the CVBs, cylindrical vector beams can be demultiplexed with high efficiency and reduced crosstalk. Furthermore, by adjusting the phase response of the vectorial diffractive element into a set of Pancharatnam–Berry (PB) phase planes, we experimentally demonstrate 11 CVBs sorting with a set of P–B phase liquid crystal devices. The proposed device may benefit the CVB-based mode multiplexing communications in future.

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A waveguide Bragg grating (WBG) can facilitate an adaptable method for glucose monitoring according to the optical properties of polymer materials. We propose the design and fabrication of a WBG for glucose monitoring. By exploiting glucose oxidase as the upper cladding, polydimethylsiloxane was used as the substrate, and polymethyl methacrylate was used as the core layer. We investigated the effects of the diffraction order, waveguide structure, and grating period on the reflected spectrum of the WBG. Finally, process reproducibility after long-term storage and the capability to eliminate background solution interference (to achieve more specific glucose detection) were evaluated. The experimental results showed that when the glucose concentration was in the range of [0, 3.6] mg/ml, as the glucose concentration increased, the wavelength decreased approximately linearly, with a sensitivity of approximately 242.9 pm/(mg/ml) in the range of 0–2.7 mg/ml, while maintaining good selectivity and stability. The WBG for glucose monitoring has the advantages of a large measurement range and high sensitivity. This approach facilitates the application potential of such polymer material-based WBG photonic sensors in wearable technology and realizes the measurement of human blood glucose.

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