Injectable, stable, and biodegradable hydrogel with platelet-rich plasma induced by l-serine and sodium alginate for effective treatment of intrauterine adhesions

Design of a double-layered material as a long-acting moisturizing hydrogel-elastomer and its application in the field protection of elephant ivories excavated from the Sanxingdui Ruins

The sudden change in the environment from a dark, low-oxygen, low-temperature, high-humidity underground stable environment to an environment with much-improved temperature and humidity, a high oxygen content, enhanced light exposure, and increased harmful organisms has greatly affected the stability of the ivory unearthed from the Sanxingdui site. Therefore, the implementation of an effective emergency protection strategy for ivory excavated at Sanxingdui is imperative and urgently needed. However, the current gauze technique used at many archaeological sites suffers from short timescales, poor transparency of the material, and susceptibility to reverse osmosis of the ivory. Therefore, in this study, a transparent poly(acrylamide-acrylic acid) (P(AM-AA)) hydrogel-poly(dimethylsiloxane) (PDMS) elastomer bilayer was designed for the effective protection of excavated ivory. In this system, a hydrophobic PDMS elastomer was constructed on the surface of the hydrogel by the introduction of a silane coupling agent to inhibit the loss of water from the hydrogel to the external environment, thus prolonging the preservation of ivory by the protective material. The covalent interface between the hydrogel and the elastomer allowed the double-layer composite to exhibit excellent interfacial bonding. In addition, the double-layer material demonstrated a high mechanical strength of 1.2 MPa and a water binding ratio of ∼31%, which allowed it to form strong hydrogen bonds with the silanol structure. When the hydrogel was placed in an air environment (temperature: 25 °C; relative humidity: 65% RH), the water-retention rate of the double-layer material was still more than 60% after 5 days, thus the double-layer material showed excellent performance. Meanwhile, the double-layer material had a transmittance of more than 90% and exhibited a high degree of transparency, which makes it possible to promptly observe the changes occurring on the surface of the ivory. The combination of the aforementioned properties makes the bilayer a promising material for moisturizing and protecting excavated ivory in situ. Based on these properties, we used the prepared P(AM-AA)/PDMS double-layer material directly for wrapping the K8 ivory with the highest water content at Sanxingdui. The weight retention rate of the ivory was around 70% after 50 days of placement (temperature: 25 °C; relative humidity: 60% RH), the macroscopic morphology did not change significantly and the mechanical properties of the wrapped ivory were basically unchanged, which indicated that the double-layer material has an excellent on-site protection effect on the ivory excavated from Sanxingdui. This work provides new ideas and methods for the temporary conservation of wet heritage.

Silicone Bioadhesive with Shear-Stiffening Effect: Rate-Responsive Adhesion Behavior and Wound Dressing Application

Stimuli-responsive adhesives with on-demand adhesion capabilities are highly advantageous for facilitating wound healing. However, the triggering conditions of stimuli-responsive adhesives are cumbersome, even though some of them are detrimental to the adhesive and adjacent natural tissues. Herein, a novel stimuli-responsive adhesive called shear-stiffening adhesive (SSA) has been created by constructing a poly(diborosiloxane)-based silicone network for the first time, and SSA exhibits a rate-responsive adhesion behavior. Furthermore, we introduced bactericidal factors (PVP-I) into SSA and applied it as a wound dressing to promote the healing of infected wounds. Impressively, the wound dressing not only has excellent biocompatibility and long-term antibacterial properties but also performs well in accelerating wound healing. Therefore, this study provides a new strategy for the synthesis of intelligent adhesives with force rate response, which simplifies the triggering conditions by the force rate. Thus, SSA has great potential to be applied in wound management as an intelligent bioadhesive with on-demand adhesion performance.

Long-lasting anti-swelling sustained-release estradiol hydrogel for promoting vaginal wound healing

This study presents a mechanically robust and stable poly(hydroxyethyl methacrylate) (PHEMA)/alginate hydrogel loaded with estrogen. The hydrogel significantly promotes vaginal wound healing in a rat vaginal loss model.