Super-resolution direct laser writing via multiphoton and peripheral photoinhibition photolithography.

Direct laser writing (DLW) with high resolution is highly desirable for fabricating arbitrary two-dimensional/three-dimensional (2D/3D) micro-/nanostructures with fine feature size for various applications. In this work, by a quasi-single-color (532 nm) dual-beam optical setup, a 100-nm lateral resolution has been achieved by both multiphoton DLW and PPI-DLW (DLW with peripheral photoinhibition), using a photoresist with a depletable photoinitiator and a radical quencher. A 120-nm lateral resolution can also be obtained even at a fast writing speed of 1000 µm/s.

Non-Covalent Interactions of Lotus Root Polysaccharides and Polyphenols and their Regulatory Mechanism on Macrophage Functions.

Despite the interaction between polyphenols and polysaccharides in food products, their specific non-covalent interactions and effects on macrophage functions are not well understood. Therefore, the interaction and mechanism of purified lotus root polysaccharide (PLRP) with polyphenols, and the regulatory mechanisms of the PLRP-polyphenol complex on the macrophage functionals were studied. By combining ferulic acid (FA) and chlorogenic acid (CHA) with PLRP, the complexes PLRP-FA, PLRP-CHA and the physical mixtures PLRP&FA and PLRP&CHA were prepared, where their mass ratios of polyphenols to PLRP were 143.

Cu(II)-catalyzed synthesis of -sulfonated quinolin-2(1)-one-3-carboxamides.

Herein, N-N bond cleavage of sulfonylhydrazides was observed and applied in the synthesis of -sulfonated quinolin-2-(1)-one-3-carboxamides. More than 30 examples were forged in 52%-97% yields. Further transformation delivered a 3,4-dihydro-quinolin-2(1)-one derivative.

Ultra-high precision nano additive manufacturing of metal oxide semiconductors via multi-photon lithography.

As a basic component of the versatile semiconductor devices, metal oxides play a critical role in modern electronic information industry. However, ultra-high precision nanopatterning of metal oxides often involves multi-step lithography and transfer process, which is time-consuming and costly. Here, we report a strategy, using metal-organic compounds as solid precursor photoresist for multi-photon lithography and post-sintering, to realize ultra-high precision additive manufacturing of metal oxides.

Light and matter co-confined multi-photon lithography.

Mask-free multi-photon lithography enables the fabrication of arbitrary nanostructures low cost and more accessible than conventional lithography. A major challenge for multi-photon lithography is to achieve ultra-high precision and desirable lateral resolution due to the inevitable optical diffraction barrier and proximity effect. Here, we show a strategy, light and matter co-confined multi-photon lithography, to overcome the issues via combining photo-inhibition and chemical quenchers.

Twisted Optical Micro/Nanofibers Enabled Detection of Subtle Temperature Variation.

The detection of subtle temperature variation plays an important role in many applications, including proximity sensing in robotics, temperature measurements in microfluidics, and tumor monitoring in healthcare. Herein, a flexible miniaturized optical temperature sensor is fabricated by embedding twisted micro/nanofibers in a thin layer of polydimethylsiloxane. Enabled by the dramatic change of the coupling ratio under subtle temperature variation, the sensor exhibits an ultrahigh sensitivity (-30 nm/°C) and high resolution (0.

Advances in the detection of β-lactamase: A review.

β-lactamase, an enzyme secreted by bacteria, is the main resistant mechanism of Gram-negative bacteria to β-lactam antibiotics. The resistance of bacteria to β-lactam antibiotics can be evaluated by testing the activity of β-lactamase. Traditional phenotypic detection is a golden principle, but it is time-consuming.

High-accuracy differential autofocus system with an electrically tunable lens.

We propose a quasi-confocal microscopy autofocus system incorporating an electrically tunable lens (ETL) to achieve differential detection. The ETL changes its focal length to collect differential curves at speeds <300 Hz, allowing selective locking onto desired focal layers and high-speed differential operations close to the locked focal plane. By segmenting the system's pupil, the interference between the outgoing and incoming near-infrared beams is avoided, thereby greatly improving the signal-to-noise ratio.

Physicochemical and Functional Changes in Lotus Root Polysaccharide Associated with Noncovalent Binding of Polyphenols.

To promote the functional applications of lotus root polysaccharides (LRPs), the effects of noncovalent polyphenol binding on their physicochemical properties, as well as antioxidant and immunomodulatory activities, were investigated. Ferulic acid (FA) and chlorogenic acid (CHA) were spontaneously bound to the LRP to prepare the complexes LRP-FA, LRP-FA, LRP-FA, LRP-CHA, LRP-CHA and LRP-CHA, and their mass ratios of polyphenol to LRP were, respectively, 121.57, 61.

3D super-resolution microscopy based on nonlinear gradient descent structured illumination.

Three-dimensional structured illumination microscopy (3D-SIM) is an essential tool for volumetric fluorescence imaging, which improves both axial and lateral resolution by down-modulating high-frequency information of the sample into the passband of optical transfer function (OTF). And when combining with the 4Pi structure, the performance of 3D-SIM can be further improved. The reconstruction results of generally used linear 3D algorithm, however, are lack of high-fidelity and proneess to generate artifacts.

Fast reconstruction algorithm for structured illumination microscopy.

Structured illumination microscopy (SIM) is a powerful technique for providing super-resolution imaging, but its reconstruction algorithm, i.e., linear reconstruction structured illumination microscopy (LRSIM) algorithm in the Fourier domain, limits the imaging speed due to its computational effort.

Three-dimensional super-resolution imaging of live whole cells using galvanometer-based structured illumination microscopy.

Imaging and tracking three-dimensional (3D) nanoscale organizations and functions of live cells is essential for biological research but it remains challenging. Among different 3D super-resolution techniques, 3D structured illumination microscopy (SIM) has the intrinsic advantages for live-cell studies; it is based on wide-field imaging and does not require high light intensities or special fluorescent dyes to double 3D resolution. However, the 3D SIM system has developed relatively slowly, especially in live imaging.

Surface wave illumination Fourier ptychographic microscopy.

We propose a novel microscopy method, combining surface wave illumination and the Fourier ptychographic microscopy (FPM) algorithm to achieve super-resolution (SR) imaging. In our system, an oil-immersion objective lens is used to excite both the total internal reflection (TIR) evanescent waves and the surface plasmon waves (SPWs), which illuminate the sample with large wave vectors. Through the FPM algorithm, a resolution approximately twice that of conventional wide-field microscopy is obtained.