Antibiotic eluting clay mineral (Laponite®) for wound healing application: an in vitro study

Abstract

Different materials in form of sponge, hydrogel and film have been developed and formulated for treating and dressing burn wounds. In this study, the potential of Laponite, a gel forming clay, in combination with an antimicrobial agent (mafenide), as a wound dressing material was tested in vitro. Laponite/mafenide (Lap/Maf) hydrogel was formulated in three different ratios of Lap/Maf 1:1, 1:2, 1:3. Laponite/mafenide/alginate (Lap/Maf/Alg) film was also formulated by combining Lap/Maf gel (1:1) with alginate. Intercalation rate of mafenide into the layers of Laponite nanoparticles and physico-chemical properties, including wound dressing characteristics of materials were studied using various analytical methods. Furthermore, the degradation of materials and the release profile of mafenide were investigated in simulated wound exudates fluid and antibacterial effectiveness of the eluted mafenide was tested on a range of bacterial species. The cytotoxicity of materials was also evaluated in skin fibroblast culture. The results showed that mafenide molecules were intercalated between the nano-sized layers of Laponite. The eluted mafenide showed active antibacterial effects against all three tested bacteria. All intercalated mafenide released from Lap/Maf 1:1 and 1:2 gel formulations and nearly 80% release from 1:3 formulation during test period. No significant difference was observed in release profile of mafenide between Lap/Maf/Alg film and Lap/Maf formulations. Wound dressing tests on Lap/Maf/Alg film showed it is a breathable dressing and has capacity to absorb wound exudates. The study showed that prepared Lap/Maf composite has the potential to be used as an antibiotic eluting gel or film for wound healing application. Additionally, Laponite has shown benefits in wound healing processes by releasing Mg(2+) ions and thereby reducing the cytotoxic effect of mafenide on fibroblast cells.

2D Nanoclay for Biomedical Applications: Regenerative Medicine, Therapeutic Delivery, and Additive Manufacturing

“…In one study, mafenide, an antibiotic used for burn wounds, was incorporated into a nanoclay-Alginate composite. [137] In media, 90% burst release of drug was observed within the first few hours, supporting cation exchange as the cations in the media replaced the intercalated mafenide. In another study, nanoclay was included in a multi-block co-polymer (pluronic) to deliver lysozyme.…”

“…This dissociation has the ability to release magnesium into a wound site, which has shown to improve the inflammatory response as well as stimulate cellular proliferation and healing. [137] The exact regulatory mechanisms of this phenomenon are currently unknown, but there is a correlation between magnesium release and wound healing rate. Therefore, based on the biophysical aspects of nanoclay, this approach has potential wound healing applications.…”

Layered Silicate-Alginate Composite Particles for the pH-Mediated Release of Theophylline

“…The combination of LP and alginate are able to provide pH-dependent sustained drug release by effectively controlling the rate of drug diffusion and water penetration that cannot be achieved from either intercalation in LP or incorporation in alginate gels alone [ 7 ]. Although drug release in this work was observed for 2 h, further sustained TP release can be expected to continue for a number of hours, based on the evidence present in the literature [ 15 , 35 ]. It may also be possible to achieve higher levels of drug release from these types of formulations by the incorporation of other large cationic molecules [ 36 ].…”

Recent developments in novel drug delivery systems for wound healing

“…When the in vivo wound healing efficacy was evaluated in full thickness excision wound model in Wistar rats, a strong scar-size decreasing effect on the wound-healing composite after operation was reported [74]. Other hydrogel systems based on polymers such as Pluronic F-127 [75], polyvinyl alcohol--sodium alginate gel-matrix system containing nitrofurazone [76] and mafenide eluting clay mineral (Laponite Ò ) [77] were also developed for wound healing applications.…”