Views: 5 Author: Site Editor Publish Time: 2021-11-10 Origin: Site
γ-PGA hydrogel is another form of γ-PGA. It is produced by gamma irradiating PGA to promote chemical cross-linking between monomer units. Microscopic examination of the γ-PGA hydrogel revealed a multi-pocket structure that can enhance water absorption due to the cross-linking of peptides.
The physicochemical properties of hydrogels enable them to absorb 5,000 times their own weight in water. The moisture content of γ-PGA hydrogel is affected by pH value and salt content. Because the molecules undergo conformational changes at acidic pH values, the specific water content and swelling degree are significantly reduced as electrolytes are added and the pH value is adjusted to an acidic environment. This allows cosmetic formulators to enhance the moisturizing ability of hair or skin formulations by adding proper electrolytes and proper pH adjustment. The release of moisture forms a protective film, which is important in applications such as masks used to moisturize the skin and reduce the appearance of wrinkles.
Compared with not using γ-PGA, the use of γ-PGA significantly reduces the loss of skin moisture. The lower concentration of PGA hydrogel and the higher concentration of glycerol produced approximately the same water retention results. This observation indicates that hydrogels have the potential to replace glycerin in cosmetic formulations.
γ-polyglutamic acid (γ-PGA) hydrogel is a material with a three-dimensional network structure cross-linked by γ-polyglutamic acid. Because the molecule contains a large number of carboxyl groups, it has good absorption capacity. Since γ-PGA is derived from microorganisms, its hydrogel is a biocompatible, environmentally friendly, and multifunctional material, which can be used in the fields of biomedicine, daily chemicals, environmental protection and textiles. Natural polyamino acid hydrogels are ideal wound dressings because of their good water solubility, biocompatibility and biodegradability.
Hydrogel based on poly(amino acid) is used as a new type of wound dressing for wound healing. The composite hydrogel is derived from water-soluble ε-polylysine and γ-poly(glutamic acid), composed of 1-ethyl-3-(3-dimethylaminopropyl)-carbodiimide and N- Hydroxy-succinimide cross-linked. The hydrogel shows excellent antibacterial effects against Escherichia coli and Staphylococcus aureus. Indirect cytotoxicity assessment showed that the composite hydrogel was non-toxic to L929 cells. By applying the composite hydrogel to the skin incision, the potential of the composite hydrogel as a wound dressing was proved. The results showed that, compared with sutures, fibrin glue and component skin adhesives, the composite hydrogel showed better healing effects and at the same time caused less inflammation. In short, the antibacterial and biocompatible ε-polylysine-γ-poly(glutamic acid) composite material may have great applications in wound healing.
A new type of multifunctional poly(γ-glutamic acid) (γ-PGA)/gelatin hydrogel has been developed and used as a wound dressing. The ideal wound dressing should effectively provide a moist environment, absorb wound exudate and protect the wound from foreign microorganisms. The sodium and calcium forms of water-soluble γ-PGA salts were chosen because of their good biocompatibility, biodegradability and water absorption capacity.