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The formation of stable blood clots or hemostasis is essential to prevent major blood loss and death from excessive bleeding. However, the body's own coagulation process is not able to accomplish timely hemostasis without the assistance of hemostatic agents. For developing novel topical hemostatic agents, tissue adhesives and sealants, it is necessary to understand the coagulation process and the hemostasis mechanism of different materials. Among hemostatic materials, polysaccharides are naturally derived polymers having excellent biodegradable and biocompatible properties. This review provides an overview of polysaccharide-based hemostatic materials and agents, including their advantages and drawbacks in hemostatic applications. Furthermore, polysaccharide-based hemostatic materials with anti-microbial and healing functions are also introduced.

Silver inlaid with gold nanoparticles (Au-Ag NPs) prepared by using egg white with an average sized of 10 nm and homogeneous dispersion were tested and presented red fluorescence. Au-Ag NPs were loaded into chitosan as wound dressing (CS-Au-Ag). CS-Au-Ag released silver ions faster, in higher amount, and in a more durable manner than chitosan dressing loaded with silver nanoparticles with the same silver content (CS-Ag), consequently, showing enhanced antibacterial activity. Cytotoxicity tests indicated that CS-Au-Ag showed low cytotoxicity to L929 cells similar to CS-Ag. These data suggest that cytotoxicity, which restricts further application of silver NPs, can be eliminated by decreasing the silver content. CS-Au-Ag presented rich and well-distributed pores, good mechanical properties, and enhanced swelling and retention properties, contributing to keeping the wound moist in the presence of residual egg white. Altogether, our results suggest that CS-Au-Ag greatly promoted wound healing compared to CS-Ag in vivo, demonstrating that CS-Au-Ag presents great potential for wound dressing, promoting wound healing.

Two‐dimensional (2D) covalent organic frameworks (COFs) feature open and ordered one‐dimensional column nanochannels which offer immense possibilities for incorporation of various guests for specific functions. However, the relatively low chemical stability of most COFs originating from the dynamic covalent linkages hinders their practical application. In this work, a highly crystalline and heteroporous dibenzo[g,p]chrysene‐based COF (DBC‐2P) was synthesized and served as a host material for ionic conduction. DBC‐2P exhibits excellent stability both in strong acid and base due to the large conjugated DBC‐based knot that reinforces the interlayer interactions. Subsequent encapsulation of linear polyethylene glycol (PEG) and PEG‐LiBF4 salt into the nanochannels of DBC‐2P affords a hybrid material with a high ionic conductivity of 2.31×10−3 S cm−1. This work demonstrates an efficient post‐synthetic strategy for the development of new COF–polymer composites with intriguing properties.

Hemostatic microparticles (HMs) have been widely used in surgery. To improve the comprehensive performance of HMs, multifunctional HMs named HM15 and HM15′ are prepared from starch, carboxymethyl chitosan, hyaluronic acid, and tannic acid. Herein, tannic acid is used as an effective cross‐linker. A 3D network structure for cell growth and wound repair can be formed by secondary cross‐linking. Through synergistic effect of these natural materials, the process of wound healing can be regulated controllably. HM15 and HM15′ have the ability of rapid hemostasis. Moreover, HM15′ shows excellent properties in antibacteria and wound healing acceleration. Blood clotting time treated with different HMs is shortened obviously from 436.8 s to 126 s. Compared with Celox, HM15 and HM15′ exhibited better broad spectrum antibacterial activity against both Escherichia coli and Staphylococcus aureus. Notably, the wound can be repaired rapidly by HM15′ in 14 days. These multifunctional HMs might have an important prospect in clinical application.

Black TiO2 has triggered worldwide research interest due to its excellent photocatalytic properties. However, the understanding of its structure–property relationships and a more effective, facile and versatile method to produce it remain great challenges. We have developed a facile approach to synthesize black TiO2 nanoparticles with significantly improved light absorption in the visible and infrared regions. The experimental results show that oxygen vacancies are the major factors responsible for black coloration. More importantly, our black TiO2 nanoparticles have no Ti3+ ions. These oxygen vacancies could introduce localized states in the bandgap and act as trap centers, significantly decreasing the electron–hole recombination. The photocatalytic decomposition of both rhodamine B and methylene blue demonstrated that, under ultraviolet light irradiation, better photocatalytic performance is achieved with our black TiO2 nanoparticles than with commercial TiO2 nanoparticles.

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