In Situ Formation of Injectable Gelatin Methacryloyl (GelMA) Hydrogels for Effective Intraocular Delivery of Triamcinolone Acetonide

Abstract

A novel drug delivery system designed for intraocular injection, gelatin methacryloyl (GelMA), has attracted much attention due to its sustained-release character and low cytotoxicity. We aimed to explore the sustained drug effect of GelMA hydrogels coupled with triamcinolone acetonide (TA) after injection into the vitreous cavity. The GelMA hydrogel formulations were characterized using scanning electron microscopy, swelling measurements, biodegradation, and release studies. The biological safety effect of GelMA on human retinal pigment epithelial cells and retinal conditions was verified by in vitro and in vivo experiments. The hydrogel exhibited a low swelling ratio, resistance to enzymatic degradation, and excellent biocompatibility. The swelling properties and in vitro biodegradation characteristics were related to the gel concentration. Rapid gel formation was observed after injection, and the in vitro release study confirmed that TA-hydrogels have slower and more prolonged release kinetics than TA suspensions. In vivo fundus imaging, optical coherence tomography measurements of retinal and choroid thickness, and immunohistochemistry did not reveal any apparent abnormalities of retinal or anterior chamber angle, and ERG indicated that the hydrogel had no impact on retinal function. The GelMA hydrogel implantable intraocular device exhibited an extended duration, in situ polymerization, and support cell viability, making it an attractive, safe, and well-controlled platform for treating the posterior segment diseases of the eye.

Unveiling the versatility of gelatin methacryloyl hydrogels: a comprehensive journey into biomedical applications

“…Rapid formation of gel postinjection and drug release assay, in vitro, affirmed that TA-hydrogels showed slower and further prolonged release kinetics in contrast to TA suspensions. The in vivo assessments indicated no evident abnormalities in retinal or anterior chamber angle conditions, substantiating the hydrogel's safety and assisting with cell viability (as shown in figure 2(ii)) [71].…”

l-Carnosine loaded on carboxymethyl cellulose hydrogels for promoting wound healing

“…The ESRs of the CMC hydrogel and CRN@hydrogel were considerably higher than those reported for some previously studied hydrogels (Table 1). 65–67 The high swelling behavior observed in the prepared hydrogels may be ascribed to the intrinsic hydrophilic nature of CMC, facilitated by the hydrogen bonding interactions between the carboxylate groups and water molecules. 68 Hydrogel materials exhibiting a high water-absorption capacity are conducive to the absorption of wound exudates.…”

Injectable smart stimuli-responsive hydrogels: pioneering advancements in biomedical applications

“…For example, Shen et al prepared an injectable in situ -forming hydrogel with GelMA to achieve a sustained release of triamcinolone acetonide in the vitreous cavity. 200 After intravitreal injection, this hydrogel could form gel in situ at the injection site after a 60-second exposure to visible light at a wavelength of 405 nm, and provided a safe, biocompatible and controlled drug-release platform in a posterior vitreous location for ophthalmic applications. Similarly, HA can also be modified to HAMA through the same chemical modification of the active groups (such as hydroxy and carboxyl groups) contained in the backbone, and acquire stronger crosslinking and mechanical properties.…”