Amoxicillin Oral Mucoadhesive Slow and Fast Release Patch: an in-Vitro Study

Objectives: Oral mucoadhesive patches offer advantages over other drug delivery methods, such as IV or peroral routes. Hydroxypropyl methylcellulose (HPMC) is frequently used in oral pharmaceutical formulations due to its patch-forming properties. Amoxicillin, a broad-spectrum antibiotic, is commonly used in dentistry to treat bacterial infections. The aim of this study is to optimize fast- and slow-release mucoadhesive patches for effective bacterial infection treatment.
Methods: Bilayer mucoadhesive patches with amoxicillin (1.5mg-per-patch) were prepared using the solvent casting method, incorporating HPMC polymers (K4M, E15, E5) and ethyl cellulose (EC) as the backing layer to control drug release. Drug release from bilayers patches was compared. All patches' thickness, folding endurance, and in-vitro drug release in deionized water and artificial saliva (AS7) were measured at various intervals using UV-Vis detection. Compatibility and form of amoxicillin were analysed with X-ray diffraction (XRD), Fourier Transform Infrared Spectroscopy (FTIR), and scanning electron microscopy (SEM).
Results: The folding endurance of all patches exceeded 300 cycles. Average patch thicknesses for monolayers were 0.399±0.066 mm (K4M), 0.334±0.024 mm (E15), and 0.375±0.055 mm (E5) and 0.471±0.019 mm (EC). The average surface pH of HPMC patches was 6.57±0.02. The K4M patch exhibited a cumulative drug release of 95.2% at 300 minutes, while E15 reached 87.7% at 60 minutes and E5 released 100% at 60 minutes. The FTIR, XRD, and SEM analyses are ongoing.
Conclusions: The mucoadhesive patches effectively controlled amoxicillin release, with K4M providing the slowest release. They showed favourable physical and mechanical properties, suggesting potential for targeted antimicrobial delivery in dental treatments. Further studies are required to evaluate microbiological efficacy and optimize formulations for clinical trials.