Development of a Biodegradable Patch Based on Polysaccharides

Area of Science:

• Biomaterials Science
• Polymer Chemistry
• Drug Delivery Systems

Background:

• Hydrogels are crucial for wound care and transdermal delivery due to their high water content and biocompatibility.
• Developing stable, responsive, and non-toxic hydrogel formulations remains a key challenge.

Purpose of the Study:

• To fabricate and characterize novel transdermal hydrogel films using gellan gum, chitosan, and agar-agar.
• To evaluate the structural integrity, pH-responsive swelling, mechanical properties, and drug release kinetics of the developed hydrogels.
• To confirm covalent crosslinking and network formation using spectroscopic and microscopic techniques.

Main Methods:

• Hydrogel films synthesized using gellan gum, chitosan, and agar-agar with glutaraldehyde crosslinking.
• Fourier-transform infrared (FTIR) spectroscopy to confirm chemical crosslinking.
• Scanning electron microscopy (SEM) for morphological analysis.
• Swelling studies conducted at different pH values (4.01 and 9.18).
• Mechanical testing to determine tensile strength and elongation.
• In vitro drug release studies using methylene blue at controlled temperatures.

Main Results:

• FTIR confirmed covalent network formation via Schiff-base reactions, indicated by a C=N peak at 1630 cm⁻¹.
• SEM revealed a homogeneous porous structure (45-120 μm) facilitating moisture absorption and diffusion.
• High pH-responsive swelling observed: 410 ± 12% at pH 9.18 and 275 ± 9% at pH 4.01.
• Mechanical properties: 0.82 ± 0.03 MPa tensile strength and 42 ± 2% elongation, ensuring skin applicability.
• Temperature-controlled release of methylene blue reached 78 ± 4% at 40 °C after 24 hours, indicating diffusion-controlled release.

Conclusions:

• The fabricated gellan-chitosan-agar hydrogel films demonstrate excellent structural stability and biocompatibility without metal ions.
• The hydrogels exhibit significant pH-responsive swelling and suitable mechanical properties for transdermal applications.
• The developed hydrogel platform is effective for controlled transdermal drug delivery, showing promise for advanced wound care solutions.