Document Type : Research Paper

Authors

• Sara Janghorban-Laricheh
• Moslem Tavakol

Department of Chemical and Polymer Engineering, Yazd University, Yazd, Iran

Abstract

Nowdays, in situ forming hydrogels have attracted increasing attentions in wound healing. In the present study, new in situ forming composite hydrogels consisted of tyramine functionalized gum tragacanth (TA-GT), hydroxyapatite particles (HAPs) and doxycycline (DX) were prepared. Hydrogel formation was realized via oxidative coupling reaction between tyramine groups of TA-GT, catalyzed by horseradish peroxidase/H2O2 system. In order to protect DX from possible side reactions during the gel formation and to achieve sustained release of DX, the drug was first loaded into hydroxyapatite particles and then DX loaded hydroxyapatite particles (DX-HAps) were encapsulated within the hydrogels. Drug content and drug loading efficiency of HAPs as well as gelation time, morphology, enzymatic degradation, swelling degree, drug release rate, cytotoxicity and antimicrobial properties of the hydrogels were evaluated. According to the results, drug content decreased and drug loading efficiency increased with increasing of DX concentration in adsorption media. The addition of HAps led to an increase in gelation time and a decrease in the pore size of TA-GT hydrogels. No burst release of DX was observed from the composite hydrogels containing DX-HAps. Also, drug release rate from these hydrogels was considerably slower than DX-HAps. The composite hydrogels containing DX-HAps showed proper antimicrobial activity against Escherichia coli and Staphylococcus aureus. The results of MTT assay, demonstrated excellent biocompatibility of the hydrogels. These results suggested that the prepared in situ forming composite hydrogels hold great potential for wound healing and might be further characterized by in vivo tests.

Keywords

• Tragacanth'
• Hydroxyapatite'
• ,'
• Doxycycline'
• In-situ forming hydrogel'
• , '
• Wound healing'
• '

Main Subjects

• Biotechnology