Porous carbon nanosphere-based imprinted composite membrane for selective and effective separation of dibenzothiophene

Constructing molecularly imprinted membranes with instant noodles-like structure for selectively separating acteoside

Acteoside (ACT) was the main bioactive components in phenylethanoid glycosides of Cistanche tubulosa. Currently, the development of an efficient method for selectively separating ACT was crucial. Consequently, yolk-shell magnetic mesoporous carbon (YSMMC) was synthesized as a nanofiller to prepare molecularly imprinted membranes (ACT-MIMs) with instant noodles-like structure for selectively separating ACT. The numerous YSMMC were moved to the upper surface of ACT-MIMs by magnetic guidance and constructed the instant noodles-like structure in ACT-MIMs. The instant noodle-like structure increased the surface roughness of ACT-MIMs, which was conducive to improving the effective imprinted interface, increasing the selectivity of ACT-MIMs. In addition, the instant noodle-like structure had dendritic interleaved pathways in ACT-MIMs. The dendritic interleaved pathways can intercept ACT through ACT-MIMs, enhancing the permselectivity of ACT-MIMs. The prepared YSMMC possessed the dendritic shell and interlayer cavity structure can provide a great accommodation space, improving the rebinding capacities of ACT-MIMs. The high permselectivity (14.49), remarkable selectivity (7.52), and excellent rebinding capacity (120.48 mg/g) were achieved for the prepared ACT-MIMs. Thus, the design of ACT-MIMs with the instant noodles-like structure were valuable for selectively separating of bioactive components.

An antibacterial packaging film based on amylose starch with quaternary ammonium salt chitosan and its application for meat preservation

A new generation of food packaging films is gradually replacing traditional plastic packaging films because of their biodegradability, safety, and some functional properties such as anti-bacterial and oxidant resistance. In the present work, an antibacterial packing film based on amylose starch and 2-hydroxypropyl-trimethylammonium chloride chitosan (HTCC) was prepared for meat preservation. The interfacial bonding mechanism between amylose, HTCC, and glutaraldehyde (GA) was determined experimentally and through molecular dynamics (MD) simulation. The macromolecular chains of amylose starch and HTCC became entangled via inter-molecular H-bonds and then cross-linked with GA via the Schiff base reaction. The interaction of amylose starch and HTCC improved the mechanical properties of the amylose films. Compared with the amylose films, the tensile strength and elongation at break of the optimal HTCC/amylose films reached to 16.13 MPa (an increase of 206.65 %) and 53.86 % (an increase of 109.49 %). The HTCC/amylose films were found to provide obvious bacteriostatic performance, a relatively low cytotoxicity, the lower transmittance in the UV region, and thus the ability to enhance the preservation of fresh meat. These excellent characteristics therefore suggest that HTCC/amylose films might be promising candidates for application in antibacterial food packaging films.

Surface Modification of Super Arborized Silica for Flexible and Wearable Ultrafast-Response Strain Sensors with Low Hysteresis

Conductive hydrogels exhibit high potential in the fields of wearable sensors, healthcare monitoring, and e-skins. However, it remains a huge challenge to integrate high elasticity, low hysteresis, and excellent stretch-ability in physical crosslinking hydrogels. This study reports the synthesis of polyacrylamide (PAM)-3-(trimethoxysilyl) propyl methacrylate-grafted super arborized silica nanoparticle (TSASN)-lithium chloride (LiCl) hydrogel sensors with high elasticity, low hysteresis, and excellent electrical conductivity. The introduction of TSASN enhances the mechanical strength and reversible resilience of the PAM-TSASN-LiCl hydrogels by chain entanglement and interfacial chemical bonding, and provides stress-transfer centers for external-force diffusion. These hydrogels show outstanding mechanical strength (a tensile stress of 80-120 kPa, elongation at break of 900-1400%, and dissipated energy of 0.8-9.6 kJ m-3 ), and can withstand multiple mechanical cycles. LiCl addition enables the PAM-TSASN-LiCl hydrogels to exhibit excellent electrical properties with an outstanding sensing performance (gauge factor = 4.5), with rapid response (210 ms) within a wide strain-sensing range (1-800%). These PAM-TSASN-LiCl hydrogel sensors can detect various human-body movements for prolonged durations of time, and generate stable and reliable output signals. The hydrogels fabricated with high stretch-ability, low hysteresis, and reversible resilience, can be used as flexible wearable sensors.