Thermosensitive Chitosan-Containing Hydrogels: Their Formation, Properties, Antibacterial Activity, and Veterinary...

Area of Science:

• Materials Science
• Biomedical Engineering
• Veterinary Medicine

Background:

• Chitosan hydrochloride (CS·HCl) and Pluronic F-127 (Pl F-127) are biocompatible polymers with potential for drug delivery.
• Thermosensitive hydrogels offer controlled release and in situ formation capabilities.
• Mucoadhesion is crucial for localized drug delivery and therapeutic efficacy.

Purpose of the Study:

• To formulate and characterize thermosensitive mucoadhesive hydrogels based on CS·HCl and Pl F-127.
• To investigate the effect of D-ascorbic acid on hydrogel properties and mucoadhesion.
• To evaluate the antibacterial activity and therapeutic potential of the developed hydrogels in veterinary medicine.

Main Methods:

• Vibrational and rotational viscometry were used to determine optimal hydrogel formulations.
• Thermosensitive transition temperatures and mechanical properties were assessed.
• Mucoadhesion was quantified by measuring pull-off force and work of adhesion.
• Antibacterial activity was tested against Gram-negative and Gram-positive bacteria.
• In vivo studies were conducted on cows with mixed bacterial infections.

Main Results:

• An optimal CS·HCl:Pl F-127 ratio (30:70) and CS·HCl concentration (3 wt.%) yielded a thermosensitive hydrogel.
• The hydrogel transitioned from a viscous liquid at 4 °C to a stable gel at 37 °C.
• D-ascorbic acid significantly enhanced mucoadhesion (Fmax: 1.5 to 4.1 kN/m², W: 66.6 to 145.1 × 10⁻³ J).
• The hydrogel exhibited high antibacterial activity and demonstrated significant therapeutic effects in treating bovine bacterial infections.

Conclusions:

• CS·HCl:Pl F-127 hydrogels are promising thermosensitive and mucoadhesive materials.
• D-ascorbic acid incorporation optimizes hydrogel performance for enhanced mucoadhesion.
• These hydrogels possess significant antibacterial properties and therapeutic potential for veterinary applications.
• The developed hydrogels could serve as independent veterinary drugs or pharmaceuticals.