Cationic Supramolecular Hydrogels for Overcoming the Skin Barrier in Drug Delivery

Abstract

A cationic bis‐imidazolium‐based amphiphile was used to form thermoreversible nanostructured supramolecular hydrogels incorporating neutral and cationic drugs for the topical treatment of rosacea. The concentration of the gelator and the type and concentration of the drug incorporated were found to be factors that strongly influenced the gelling temperature, gel‐formation period, and overall stability and morphology. The incorporation of brimonidine tartrate resulted in the formation of the most homogeneous material of the three drugs explored, whereas the incorporation of betamethasone resulted in a gel with a completely different morphology comprising linked particles. NMR spectroscopy studies proved that these gels kept the drug not only at the interstitial space but also within the fibers. Due to the design of the gelator, drug release was up to 10 times faster and retention of the drug within the skin was up to 20 times more effective than that observed for commercial products. Experiments in vivo demonstrated the rapid efficacy of these gels in reducing erythema, especially in the case of the gel with brimonidine. The lack of coulombic attraction between the gelator–host and the guest–drug seemed particularly important in highly effective release, and the intermolecular interactions operating between them were found to lie at the root of the excellent properties of the materials for topical delivery and treatment of rosacea.

Topical Mucoadhesive Alginate-Based Hydrogel Loading Ketorolac for Pain Management after Pharmacotherapy, Ablation, or Surgical Removal in Condyloma Acuminata

“…The experiment was conducted as designed for the release assay except that 500-µm dermatomed frozen skin was used instead of synthetic membrane ( n = 6). The skin was thawed at room temperature, and skin discs were punched and mounted on the Franz cell (0.64 cm 2 of diffusion area) with the Stratum Corneum facing up to the donor compartment and the dermis in contact with the receptor fluid [ 35 ]. Hydrogel (200 mg) was applied to the skin, and samples (300 µL) were collected at the time intervals: 0, 3, 6, 8, 10, 19.75, 20.75, and 24 h and stored at −20 °C until sample analysis by HPLC was carried out.…”

Phenylboronic Acid Functionalized Polycarbonate Hydrogels for Controlled Release of Polymyxin B in Pseudomonas Aeruginosa Infected Burn Wounds

“…Hydrogels are 3D hydrophilic crosslinked polymer networks, conventionally attractive for their high water content and viscoelastic properties . Majority of existing hydrogels for cutaneous applications are prepared via physical crosslinking techniques of polymeric subunits given their degradability and absence of toxic chemical crosslinkers . Nevertheless, physically crosslinked hydrogels have poor mechanical stability which limits their utility as controlled drug delivery systems .…”

Human Skin Permeation Studies with PPARγ Agonist to Improve Its Permeability and Efficacy in Inflammatory Processes

“…Skin color determinations were performed after 5, 10, and 20 min of treatment. Colors were reproduced using Microsoft Excel ® software (Version 2016, Microsoft Corporation, Redmond, WA, USA) from the RGB codes and plotted as a sequence and evaluated in accordance with previously mentioned equations [ 67 ].…”