In Situ‐Forming Glucose‐Responsive Hydrogel from Hyaluronic Acid Modified with a Boronic Acid Derivative

Abstract

Hydrogels are a promising class of biomaterials for sustained drug release applications. The use of covalently cross‐linked hydrogels for drug delivery applications may be limited due to their manufacturing complexity and the high injection forces required for their administration. Stimulus‐responsive hydrogels, which are engineered to respond to stimuli such as pH, temperature, ionic strength, or chemical potential, may overcome these shortcomings and enable the development of injectable hydrogels. This study presents a strategy for forming hydrogels such that a sol–gel transition occurs in response to physiologically relevant glucose concentrations. A hyaluronic acid (HA) polymer backbone is modified with 3‐aminophenylboronic acid, which is able to reversibly bind glucose with a 2:1 stoichiometry. The boronic acid‐functionalized polymer is demonstrated to be glucose responsive, as indicated by its spontaneous hydrogelation and subsequent increase in stiffness as a function of glucose concentration. Furthermore, the transient nature of the boronic acid‐glucose cross‐linking enables the hydrogel to self‐heal after physical rupture. A proof‐of‐concept gelation in alkaline conditions is demonstrated, but the system may be adapted for gelation at physiological pH using modified boronic acids. These HA–boronic acid conjugates have potential utility as in situ‐forming hydrogels for sustained drug release applications.

Preparation of P(EGDMA‐co‐VPBA) Adsorbent and Its Application in the Separation of Steviol Glycosides

“…As we all know, the structure and functional group of organic polymer adsorbent are the keys to measuring the adsorption performance. [30,31] For instance, the boric acid affinity hierarchical porous metal-organic framework was synthesized by Tan's group, which has good adsorption performance to separation teicoplanin because of the large pore diameter and boric acid affinity. [8] Also, Liu prepared modifying cotton wool with boric acidfunctionalized titania nanomaterial.…”

Stimuli-Responsive Polymers Providing New Opportunities for Various Applications

“…The formation of the hydrophilic structure triggers changes in polymers of different architectures. For example, it triggers changes such as swelling in hydrogels [461], (Figure 28), reversible gel formation [462][463][464], self-assembly and disassembly behaviors in block copolymers [465][466][467][468][469][470][471][472][473], surface studies [474,475], film thickness and pore size changes [459,476,477]. If insulin is included in the polymeric system, insulin is released and its use in diabetes is provided [471,478].…”

Diol responsive viscosity increase in a cetyltrimethylammonium bromide/sodium salicylate/3-fluorophenylboronic acid micelle system

“…Utilising this change, PBA has been studied as a sugar sensor for analytical chemistry and supramolecular assemblies. 15–17 Sugar-responsive viscoelastic systems 18–21 are desired for applications in fields such as drug delivery, analytical chemistry, cell engineering or medical engineering. Recently, novel sugar-responsive WLMs composed of a PBA or PBA derivative and a cationic surfactant, cetyltrimethylammonium bromide (CTAB, Fig.…”