Preparation of chitosan functionalized end-capped Ag-NPs and composited with Fe3O4-NPs: Controlled release to pH-responsive delivery of progesterone and antibacterial activity against pseudomonas aeruginosa (PAO-1)

In this work, functionalized chitosan end-capped Ag nanoparticles (NPs) and composited with Fe3O4-NPs was prepared as pH-responsive controlled release carrier for gastric-specific drug delivery. The structure of prepared material was characterized by FE-SEM, XRD, EDS and FT-IR analysis. The loading behavior of the progesterone onto this novel material was studied in aqueous medium at 25 degrees C and their release was followed spectrophotometrically at 37 degrees C in seven different buffer solutions (pH1.2, 2.2, 3.2, 4.2, 5.2, 6.2 and 7.2) to simulate intestine and gastric media which experimental results reveal more release rate in pH1.2 (gastric medium) with respect to other buffers. This observation is attributed to dependency of the CS-IMBDO-Ag-Fe3O4-NPs and progesterone structure with buffer pH that candidate this new material as prospective pH-sensitive carrier for gastric-targeted drug delivery. On the other hand, the antibacterial properties of this material against gram-negative bacterium pseudomonas aeruginosa (PAO-1) in agar plates was studied and accordingly based on broth micro dilution the minimum bactericidal concentration (MBC) and minimum inhibitory concentration (MIC) with respect to standard CLSI in different concentrations of CS-IMBDO-Ag-Fe3O4-NPs was calculated. The results reveal that MIC and MBC values are 50 and 1250g/mL, respectively. In addition, extracts of Portulaca oleracea leaves was prepared and its antibacterial activity in single and binary system with CS-IMBDO-Ag-Fe3O4-NPs as synergies effect against PAO-1 was tested and results shown that these materials have significant synergistic effect for each other.