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Conventional wound-dressing materials with structural and functional deficiencies are not effective in promoting wound healing. The development of multifunctional wound dressings is emerging as a promising strategy to accelerate blood coagulation, inhibit bacterial infection, and trigger full-thickness wound into a regenerative process. Herein, multifunctional composite sponges were developed by incorporation of traditional Chinese medicine Kangfuxin (KFX) into alginate (AG)/carboxymethyl chitosan (CMC) via green crosslinking, electrostatic interaction, and freeze-drying methods. It is demonstrated that the AG/CMC/KFX (ACK) sponges exhibit a highly interconnected and porous structure, suitable water vapor transmittance, excellent elastic properties, antibacterial behavior, cytocompatibility, and rapid hemostasis. Further, in a rat full-thickness wounds model, the ACK sponge containing 10% KFX (ACK-10) significantly facilitates wound closure compared to the AC group and ACK sponge containing 5% and 15% KFX. Thus, the multifunctional ACK-10 composite sponge has great promise for the application of full-thickness wound healing., Competing Interests: Declaration of competing interest The authors declare no competing financial interest., (Copyright © 2020. Published by Elsevier B.V.)

Objective: To analyze standards of alginate-based medical devices at home and abroad, and to emphasize key issues of quality control that should be concerned about., Methods: Based on investigation of alginate application in medical devices and alginate-related medical standards, alginate-related technical indicators and quality control points were comprehensively analyzed., Results: With the rapid development of alginate-based medical materials and medical devices, the relevant standards at home and abroad have been elaborated on the basic technical indicators and detection methods. In addition to Chinese Pharmacopoeia, China has issued one alginate standard for tissue engineering and three alginate related product standards., Conclusion: Considering the special physical and chemical properties of alginate, researchers also need to focus on the sterilization method, expiry date, molecular weight, and ratio of α-L-guluronic acid to β-D-mannuronic acid of alginate, and impurity content.

Indirect cell contact co-culture system is increasingly becoming more attractable owing to their advantages of easy cell separation and desirable outcomes for cell-cell interactions. However, how to precisely control the spatial position of cells within multicellular co-cultures is still experimentally challenging due to the incapability of the conventional methods in vitro. In the present study, a tunable collagen/alginate-chitosan (Col/Alg-Chi) membrane was established, which was capable of controlling intercellular distance between the neighboring cells at a level of micrometer resolution. It was showed that intercellular distance between the hepatocytes and the fibroblasts exerted significant influence on hepatic function in vitro. In particular, maintenance of the functionality of primary hepatocytes requires direct contact between the hepatocytes and their supportive stromal cells, and their effective contact distance is within 30μm. This technical platform would potentially enable investigations of dynamic cell-cell interaction in a multitude of applications including organogenesis, development or even neoplastic transformation., (Copyright © 2016. Published by Elsevier Ltd.)

Developing bio-multifunctional wound dressings with excellent hemostasis, antibacterial, anti-inflammatory, enhanced angiogenesis and hair follicle regeneration for promoting full-thickness wound healing is highly valuable in clinical application. Herein, bio-multifunctional composite sponges were prepared by coupling alginate and chitosan with fucoidan through electrostatic interaction, Ca2+ crosslinking, and lyophilization processes. The prepared alginate/chitosan/fucoidan (ACF) sponges display excellent elastic properties, preserving their shape even after bending and compressive strain without failure. The ACF sponge containing 10% fucoidan (ACF-1) shows better hemostatic and antibacterial performances, and significantly promotes wound closure in a rat full-thickness wounds model compared to the alginate/chitosan group and ACF sponge containing 30% fucoidan. Furthermore, the ACF-1 sponge greatly facilitates the epithelialization and the formation of collagen in the dermis, promotes the hair follicle regeneration, enhances vascularization by upregulating the protein expression of CD31, and reduces inflammation by downregulating the protein expression of TNF-α. This work suggests that ACF sponges with a certain amount of fucoidan display great potential for the treatment of full-thickness skin repair. Unlabelled Image • Bio-multifunctional ACF sponges were successfully prepared through a facile, efficient, green cross-linked, and freeze-drying processes. • The ACF sponges possessed excellent hemostatic and antibacterial performances as well as greatly promoted full-thickness wound healing. • The ACF sponges reduced inflammation, facilitated the epithelialization, as well as enhanced angiogenesis and hair follicle regeneration. [ABSTRACT FROM AUTHOR]