Smart release of antimicrobial ZnO nanoplates from a pH-responsive keratin hydrogel

Abstract

A smart antibacterial biomaterial based on a keratin hydrogel with pH-dependent behavior and Zinc Oxide nanoplates as biocide agent has been developed. The pH of a chronic wound is basic due to bacterial metabolism. Originally shrank at acid pH, keratin hydrogels swell upon contact with a bacterial contaminated media leading to the release of the nanoparticles. The material has been thoroughly characterized by infrared spectroscopy, Raman, scanning electron microscope, swelling behavior, Differential scanning calorimetry, Small-angle X-ray scattering, rheology, antimicrobial activity and cytotoxicity. The results show that 5% of Zinc Oxide nanoparticles concentration is the optimum for wound dressing applications.

Recent trends in protein and peptide-based biomaterials for advanced drug delivery

“…At a basic pH, hydrogen bonds broke to create more sites for water adsorption, thus forcing chain reorganization and allowing the material to swell [ 121 ]. Villanueva et al expanded upon this work by incorporating antimicrobial ZnO nanoplates into the pH-responsive hydrogel [ 122 ]. Upon administration to a chronic wound, the hydrogel swelled in response to the basic environment and locally released the biocidal agent.…”

“…Upon administration to a chronic wound, the hydrogel swelled in response to the basic environment and locally released the biocidal agent. As the wound healed and the presence of microbes decreased, the gel collapsed and inhibited the release of ZnO [ 122 ]. This study demonstrates how keratin hydrogels can be used to adjust the delivery of a therapeutic agent in response to alterations in pH.…”

Whey Proteins–Zinc Oxide Bionanocomposite as Antibacterial Films

“…It is also an effective antimicrobial agent [ 23 , 24 ], acting through three main bactericidal mechanisms: release of Zn 2+ ions, UV-enhanced production of Reactive Oxygen Species (ROS) and physical interactions with microbial cells, which are in turn influenced by the nanoparticle morphology and size [ 25 , 26 , 27 , 28 ]. It is frequently investigated for fabrication of nanocomposites for food packaging [ 29 ], antimicrobial coatings [ 30 ] and wound dressings [ 31 , 32 , 33 ].…”

Dual adsorbent-photocatalytic keratin–TiO2 nanocomposite for trimethoprim removal from wastewater

“…In addition, the ma tri x ca n contribute to the remediation process i f i t shows a ffinity for the ta rget contaminant. In these nanocomposites both a ds orption and degradation of the pollutants take place making this technology one of the most auspicious a lternatives [19][20][21][22] obta ined from waste materials of the livestock a nd poultry i ndustry s uch a s hair, wool, hooves, horns, feathers, etc [23][24][25] . Generally, the obta ined keratin materials (sponge or film s tructures) have good fl exibility but poor mechanical properties.…”