Synthesis And Characterization Of Crosslinked Chitosan/??Olyvinyl????Yrrolidone And Sodium Alginate/Chitosan Hybrid ??Ydrogels For Controlled Drug Release And Bactericidal Efficacy

Abstract

Hydrogels Have Received Much Consideration In Controlled Drug Delivery Systems For Their Exceptional Characteristics Such As Swelling, Biocompatibility, Biodegradability, And Sensetivity To External Stimuli. Ph-Sensitive Hydrogels Swell In Response To Changes In Ph And Have Been Employed In Controlled Release Applications. Despite All These Attractive Properties Of Stimuli Responsive Hydrogels, Mechanically Fragile Structures Resulting In A Rapid Burst Drug Release, Slow Responsiveness And Poor Drug Bioavailability Due To Failure Of Controlled Drug Delivery Systems Design Are Still Challenging. By Adjusting The Compositions Of The Polymers And Crosslinking Agents, Features Like Porosity, Mechanical Properties, Swelling, And Drug Release Behavior Can All Be Controlled Precisely. In This Study, ?�H-Sensitive Hybrid ??Ydrogels, Including Chitosan/Polyvinylpyrrolidone By Chemical Crosslinking Method Using Glutaraldehyde And Double-Crosslinked Chitosan/Sodium Alginate By The Ionotropic Method Using Calcium Chlorideand Glutaraldehyde As Crosslinking Agents Were Produced. The Prepared ??Ydrogels Were Applied In A Controlled-Release Study Of The Model Drugs (Metronidazole And Amoxicillin) Incorporated Into The Optimal ??Ydrogel System Using In Situ Crosslinking Method. To Optimize The ??Ydrogel Compositions Used For The Controlled Drug Release Study, Important ??Ydrogel Physicochemical Properties Such As Swelling Ratio, Porosity, And Gel Fraction With Respect To ?�Olymer Weight Ratiosand Crosslinker Concentration As Well As Biodegradation Were Evaluated. Based On Their Swellingbehavior, Chitosan/Polyvinylpyrrolidone ??Ydrogel (Weight Ratio Of 60:40) Crosslinked By 600 ??L Glutaraldehyde And A Sodium Alginate/Chitosan ??Ydrogel (Weight Ratio Of 75:25) Crosslinked With 2% Calcium Chloride Soaked In Enough Glutaraldehyde (25%, W/V) Were Chosen For An In Situ ?��Olymerization Of 200 Milligrams Each Drug. The Functional Groups Of The Polymers And Presence Of Well Defined Polymer And Drug Interactions, Improved Thermal Stabilities Of The Hydrogels Than The Polymers, Amorphous And Porous Structures Of The Hydrogels Were Confirmed By Fourier Transform Infrared Spectroscopy, Thermogravimetric Analysis, X-Ray Diffraction, And Scanning Electron Microscopy, Respectively. The Correlation Coefficient (P < 0.05) Showed A Significant Linear Dependence Of Swelling Ratio Of The ??Ydrogels And Each Drug Release Profile In All Physiological Fluids. The In Vitro Studies Revealed That The ??Ydrogels Are ?��H-Sensitive And Have Considerable Biodegradability. The Korsmeyer-???Eppas Model Is The Best Fit For The Releaseof Each Drug Following A Diffusion- And Swel