Insights into the Role of Biopolymer-Based Xerogels in Biomedical Applications

Abstract

Xerogels are advanced, functional, porous materials consisting of ambient, dried, cross-linked polymeric networks. They possess characteristics such as high porosity, great surface area, and an affordable preparation route; they can be prepared from several organic and inorganic precursors for numerous applications. Owing to their desired properties, these materials were found to be suitable for several medical and biomedical applications; the high drug-loading capacity of xerogels and their ability to maintain sustained drug release make them highly desirable for drug delivery applications. As biopolymers and chemical-free materials, they have been also utilized in tissue engineering and regenerative medicine due to their high biocompatibility, non-immunogenicity, and non-cytotoxicity. Biopolymers have the ability to interact, cross-link, and/or trap several active agents, such as antibiotic or natural antimicrobial substances, which is useful in wound dressing and healing applications, and they can also be used to trap antibodies, enzymes, and cells for biosensing and monitoring applications. This review presents, for the first time, an introduction to biopolymeric xerogels, their fabrication approach, and their properties. We present the biological properties that make these materials suitable for many biomedical applications and discuss the most recent works regarding their applications, including drug delivery, wound healing and dressing, tissue scaffolding, and biosensing.

Protecting Proteins from Desiccation Stress Using Molecular Glasses and Gels

“…Aerogels and xerogels differ in many ways. Perhaps most notably, aerogels shrink less upon drying, which leads to greater porosity, specific surface area, and a lower bulk density. ,, In fact, aerogels hold the record for the lowest density solid . Protein can be trapped in silica aerogels by first forming the hydrated gel around the protein in solution and then replacing water with ethanol with subsequent critical-point drying in an atmosphere of CO 2 .…”

Polysaccharide-Based Edible Gels as Functional Ingredients: Characterization, Applicability, and Human Health Benefits

“…Xerogels becomes denser than aerogels due to the formation of smaller pores (1–10 nm). Moreover, xerogels maintain porosity values between 15–50% alongside a lower surface area [ 8 ]. Their appearance is similar to a thin film without noticeable pores [ 59 ].…”

“…Thus, each class is characterized by specific properties. For example, xerogels are denser than aerogels [ 8 ], while cryogels has larger macropores and lower specific surface area than aerogels [ 9 ].…”

Advancements in the Use of Hydrogels for Regenerative Medicine: Properties and Biomedical Applications

“…This process is reversible, in the dry state, called xerogel, the gel is a solid material, but in the presence of water, it expands until it reaches equilibrium swelling. This latter state results from a balance between the osmotic forces that cause water to penetrate between the hydrophilic polymer chains and the cohesive forces between these chains that resist expansion [ 42 ].…”