Characteristics of Hyaluronate-hydroxyethyl Acrylate Blend Gel and Release of Cationic Amphiphilic Solutes.

Abstract

Hyaluronate-hydroxyethyl acrylate blend gel (HA-PHEA) were prepared to modify the brittleness of hyaluronate gel (HA) and the characteristics of HA-PHEA gel were compared with those of HA and polyhydroxyethyl acrylate (PHEA) gels. These gels were high in water content and transparent. HA-PHEA gel was improved in viscoelastic properties due to the elasticity and the high affinity with water of PHEA, and the drying-swelling cycles became reversible. The effective charge densities q q of the gels estimated from membrane potentials were ؊0.002, ؊0.008 and 0 mol dm ؊3 for HA-PHEA, HA and PHEA gels. Effects of electro-static and nonelectrostatic interactions on absorptions and releases were studied using sodium benzoate (NaBA) as an anionic solute, and methylene blue (MB), chlorpromazine (CPHCl) and benzethonium chloride (BZTCl) as cationic solutes, in which CPHCl and BZTCl are cationic amphiphilic solutes. The releases of MB, CPHCl and BZTCl from HA-PHEA and HA gels were suppressed comparing with those of NaBA. By adding salts, the releases of MB and CPHCl were enhanced but those of BZTCl were suppressed due to enhancement of the intra-and intermicelle formation. In the releases of the cationic solutes from HA-PHEA gel, electrostatic and nonelectrostatic interactions with HA were found to play important roles. Behaviors of the releases from HA-PHEA gel were found to possess the features of HA gel.

Hydrogels Classification According to the Physical or Chemical Interactions and as Stimuli-Sensitive Materials

“…UV radiation-induced polymerization is also frequently used to prepare hydrogels [ 92 , 93 , 94 , 95 ]. With this type of polymerization, they can be formed in situ [ 96 ], molded structures and even photoreversible systems can be prepared that photodegrade on exposure to UV light such that the release of drugs is controlled [ 97 ].…”

Green Synthetic Approach for Photo-Cross-Linkable Methacryloyl Hyaluronic Acid with a Tailored Substitution Degree

“…Due to the rapid photo-cross-linkable property, HA-MA hydrogel has been extensively used in tissue engineering applications, such as 3D cell culture scaffolds, − drug/protein delivery, − wound healing material, and corneal perforation sealing material . Generally, the methacryloyl group can be conjugated to HA chains using methacrylic anhydride ,,,− or glycidyl methacrylate (Scheme A). ,,,− Using the methacrylic anhydride method in an aqueous phase, a high molar ratio of methacrylic anhydride (20 equiv) is required, and a compromised substitution degree (SD; ≤20%) is normally achieved, due to the low solubility of methacrylic anhydride in H 2 O. ,,,, To increase SD, Rachel Auzély-Velty et al reported methacryloyl conjugation method using a mix solution of H 2 O and dimethylformamide (DMF) for dissolving HA and methacrylic anhydride, resulting in 49% of SD . Similarly, Spencer L. Fenn and Rachael A. Oldinski utilized an ion-exchange resin and a mixed solution of H 2 O and dimethyl sulfoxide to increase the solubility of HA and methacrylic anhydride .…”