Introduction: Alginate is a biocompatible polysaccharide that is commonly used in the pharmaceutical, biomedical, cosmetic, and food industries. Though solid dressings composed of alginate can absorb water and promote wound healing, they are not effective hemostatic materials, particularly against massive hemorrhage. The purpose of this study is to attempt to increase the hemostatic capabilities of alginate by means of hydrophobic modification.
View Article and Find Full Text PDFRecently there has been much interest in using light to activate self-assembly of molecules in a fluid, leading to gelation. The advantage of light over other stimuli lies in its spatial selectivity, i.e.
View Article and Find Full Text PDFPolymer hydrogels have long been used to hold and culture biological cells within their three-dimensional (3-D) matrices. Typically, in such cases, the cells are passively entrapped in a mesh of polymer chains. Here, we demonstrate an alternate approach where cells serve as active structural elements (crosslinks) within a polymer gel network.
View Article and Find Full Text PDFHydrophobically modified chitosan (hmC) is a self-assembling polymer that has attracted recent attention for many applications, including as a hemostatic agent. One limitation with chitosan and its derivatives like hmC is that these polymers are soluble in water only under acidic conditions (because the pKa of chitosan is about 6.5), which could be undesirable for biomedical applications.
View Article and Find Full Text PDFThis paper reports a simple, rapid, and sugar-selective method to induce gelation from glucose-containing samples. This method employs glucose oxidase (GOx) to selectively "recognize" and oxidize glucose to generate gluconic acid, which acts to solubilize calcium carbonate and release calcium ions. The release of calcium ions triggers gelation of the calcium-responsive polysaccharide alginate to form a calcium-alginate hydrogel.
View Article and Find Full Text PDFBiopolymers such as alginate and pectin are well known for their ability to undergo gelation upon addition of multivalent cations such as calcium (Ca(2+)). Here, we report a simple way to activate such ionic gelation by UV irradiation. Our approach involves combining an insoluble salt of the cation (e.
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