Electroresponsive and pH-Sensitive Hydrogel as Carrier for Controlled Chloramphenicol Release

Abstract

Multiresponsive hydrogels, which are smart soft materials that respond to more than one external stimulus, have emerged as powerful tools for biomedical applications, such as drug delivery. Within this context and with the aim of eliminating the systematic administration of antibiotics, special attention is being paid to the development of systems for controlled delivery of antibiotic for topical treatment of bacterial infections. In this work, an electro-chemo responsive hydrogel able to release chloramphenicol (CAM), a broad spectrum antibiotic also used for anticancer therapy, is proposed. This has been prepared by grafting poly(acrylic acid) (PAA) to sodium alginate (Alg) and in situ encapsulation of poly(3,4-ethylenedioxythiophene) nanoparticles loaded with CAM (PEDOT/CAM NPs), which were obtained by emulsion polymerization. Although the response to electrical stimuli of PEDOT was the main control for the release of CAM from PEDOT/ CAM NPs, the release by passive diffusion had a relatively important contribution. Conversely, the passive release of antibiotic from the whole engineered hydrogel system, Alg-g-PAA/PEDOT/CAM, was negligible, whereas significant release was achieved under electrostimulation in an acid environment. Bacterial tests and assays with cancer cells demonstrated that the biological activity of CAM remained after release by electrical stimulation. Notably, the successful dual-response of the developed hydrogel to electrical stimuli and pH changes evidence the great prospect of this smart material in the biomedical field, as a tool to fight against bacterial infections and to provide local cancer treatment.

Polysaccharide-Based Coating with Excellent Antibiofilm and Repeatable Antifouling-Bactericidal Properties for Treating Infected Hernia

“…In recent years, there have been numerous efforts to enhance the antimicrobial properties of medical device surfaces to combat bacterial infections; these include various strategies to control slow release with physical adsorption or loading of drugs, such as antibiotic loading, − the use of antimicrobial peptides, , metal nanoparticles, , photodynamic therapy, − and polycationic antimicrobials. − Among these approaches, quaternary ammonium polymers have demonstrated effective bactericidal activity by disrupting the cell membrane of bacteria. They provide the advantages of simple preparation, absence of drug resistance, and long-lasting antibacterial effects .…”

Double-Network Hydrogel with Strengthened Mechanical Property for Controllable Release of Antibacterial Peptide

“…As one of the substrates, AMPs form DN hydrogels with inherently antibacterial activities. Moreover, the individual AMP molecules within the DN networks might be released into the surroundings in a controlled and sustained manner, offering prolonged antibacterial duration, augmented antibacterial efficacy, and minimized systemic toxicities associated with recurrent infections and burst release. , …”

“…Moreover, the individual AMP molecules within the DN networks might be released into the surroundings in a controlled and sustained manner, 38 offering prolonged antibacterial duration, augmented antibacterial efficacy, and minimized systemic toxicities associated with recurrent infections and burst release. 39,40 Herein, a DN hydrogel, composed of the photoresponsive polymer gelatin methacryloyl (GelMA) 41 and ion-responsive AMPs (C16-WIIIKKK, termed as IK7), was developed. GelMA, a type of biocompatible and multiresponsive biomaterials, was chosen for its ability to photo-cross-link into hydrogels, thereby improving stability.…”

Advances and Trends of Photoresponsive Hydrogels for Bone Tissue Engineering

“…Stimuli-responsive hydrogels are made up of specific components that act as “on–off” sensors to detect various stimuli such as electricity, enzymes, pH, ROS, temperature, magnetic field, or light . These stimuli can induce chemical or physical changes of hydrogels reversibly or irreversibly, including degradation, shrinkage or swelling, competitive binding, sol–gel transition, and self-assembly .…”