Rheological Investigation of Thermoresponsive Alginate-Methylcellulose Gels for Epidermal Growth Factor Formulation

Abstract

Epidermal growth factors (EGF) serve as promising candidates for skin regeneration and rejuvenation products, but their instability hinders them from widespread use. Protective immobilization and directed release can be achieved through implementing a hydrogel delivery system. Alginate and methylcellulose are both natural polymers offering biocompatibility and environmental sensitivity. This blended gel system was investigated rheologically to understand its performance in topical applications. Alginate and methylcellulose were found to form a synergistic gel system that resulted in superior viscosity and thermoresponsiveness compared to the individual components. Increasing methylcellulose concentration directly enhanced gel elasticity, and higher viscosities provided better thermal protection of EGF. The addition of EGF at 3.33 mg/mL resulted in a decrease of viscosity but an increase in viscoelastic modulus. EGF concentration also played a large role in shear viscosity and thermoresponsiveness of the ternary system. An alginate-methylcellulose system presents promising rheological tunability, which may provide EGF thermal protection in a topical delivery format.

Characterization of alginate extracted from Sargassum latifolium and its use in Chlorella vulgaris growth promotion and riboflavin drug delivery

“…1,4-linked-d-mannuronic (M residues) and L-guluronic acids (G residues) represent the constituents of the linear biopolymer alginate which are partitioned into homopolymeric blocks (G- and M-blocks) and heteropolymeric blocks (MG-blocks) 3 . The viscosity as well as gel strength of the algal polysaccharide solution are affected by the type of algal polysaccharide, temperature, pH, and presence of ions such as K + and Ca 2+ 4 . Owing to pH sensitivity of the alginate (ionotropic gelation); it shrinks in an acidic medium and swells in high pH conditions 3 .…”

Modern Wound Dressings: Hydrogel Dressings

“…Semi-permeable film dressings consist of a porous transparent and adhesive polyurethane which provides an aqueous vapor transmission, O 2 and CO 2 gas exchange, autolytic scab removal, and, in addition, polyurethane films that are impermeable to bacteria [ 10 ]. Initially, similar films were made from nylon with adhesive polyurethane edges, while polyurethane was used as a backing to impart compression properties [ 13 ]. Despite the disadvantages of nylon dressings, which include insufficient absorptive capacity for them to be applied to wounds with profuse exudation, such dressings are highly elastic and can be applied to the surface of any shape; in addition, the transparency of the nylon and polyurethane film makes it possible to monitor wound healing without removing the dressing.…”

“…In comparison with traditional WDs, modern ones provide the wettability of the wound surface, gas exchange, exudate absorption, are non-adhesive to the wound surface, and are able to enhance autolytic wound debridement. Among modern WDs, hydrogel materials occupy a special niche due to the wide potential as systems for targeted delivery of drugs [ 10 ], antibiotics [ 11 ], nanoparticles [ 12 ], growth factors [ 13 ] and regulatory peptides [ 14 ]. This mini review briefly discusses both traditional and modern WDs, among which special attention is paid to hydrogels and hydrocolloids, and, in addition, the classification of hydrogels by the mechanism of gelation provided.…”

Review of Applications and Future Prospects of Stimuli-Responsive Hydrogel Based on Thermo-Responsive Biopolymers in Drug Delivery Systems

“…The BSA release was 50.0% of the loaded drug within 2 h and the system showed acceptable toxicity towards intestinal (colon) Caco-2 epithelial cells, even at high concentrations [ 35 ]. The synergistic hydrogel system made of methylcellulose and alginate showed superior thermo-responsiveness and viscosity than the individual components, and the gel system was used to load epidermal growth factors for skin regeneration [ 36 ]. The gel system is reported to provide the loaded EGF with thermal protection in a topical delivery format due to its promising rheological tenability and the system offered biocompatibility [ 36 ].…”

“…The synergistic hydrogel system made of methylcellulose and alginate showed superior thermo-responsiveness and viscosity than the individual components, and the gel system was used to load epidermal growth factors for skin regeneration [ 36 ]. The gel system is reported to provide the loaded EGF with thermal protection in a topical delivery format due to its promising rheological tenability and the system offered biocompatibility [ 36 ]. The formulation from methylcellulose and alginate showed in situ gel formation at 37 °C and was used as drug delivery systems for acetaminophen, mexiletine, metoprolol, ambroxol, loxoprofen, theophylline, ketotifen, and salbutamol [ 37 ].…”