Abstract
This present work was aimed at synthesizing pH-sensitive cross-linked AA/Gelatin hydrogels by free radical polymerization. Ammonium persulfate and ethylene glycol dimethacrylate (EGDMA) were used as initiator and as cross-linking agent, respectively. Different feed ratios of acrylic acid, gelatin, and EGDMA were used to investigate the effect of monomer, polymer, and degree of cross-linking on swelling and release pattern of the model drug. The swelling behavior of the hydrogel samples was studied in 0.05 M USP phosphate buffer solutions of various pH values pH 1.2, pH 5.5, pH 6.5, and pH 7.5. The prepared samples were evaluated for porosity and sol-gel fraction analysis. Pheniramine maleate used for allergy treatment was loaded as model drug in selected samples. The release study of the drug was investigated in 0.05 M USP phosphate buffer of varying pH values (1.2, 5.5, and 7.5) for 12 hrs. The release data was fitted to various kinetic models to study the release mechanism. Hydrogels were characterized by Fourier transformed infrared (FTIR) spectroscopy which confirmed formation of structure. Surface morphology of unloaded and loaded samples was studied by surface electron microscopy (SEM), which confirmed the distribution of model drug in the gel network.
Highlights
Stimuli-responsive polymers offer a drug delivery platform that can be utilized to deliver drugs at a controlled rate and in a stable and biologically active form
PH sensitive cross-linked acrylic acid (AA)/Gelatin hydrogels were prepared by free radical polymerization using ethylene glycol dimethacrylate (EGDMA) as cross-linking agent as a carrier for water soluble drugs
While with the increase of acrylic acid contents in the composition, the dynamic and equilibrium swelling ratio increased due to the electrostatic repulsion between carboxylate ions (COO−) which leads to chains repulsion and in turn swelling of the network at higher pH values
Summary
Stimuli-responsive polymers offer a drug delivery platform that can be utilized to deliver drugs at a controlled rate and in a stable and biologically active form. These polymers respond to small changes in environmental conditions, such as temperature, pH, light, ionic strength, electric or magnetic fields, or the presence of enzymes or specific ligands. Hydrogels are three-dimensional hydrophilic polymer networks that swell in water or biological fluid without dissolving due to chemical or physical cross-links [1] These three-dimensional networks of a hydrogel are formed by either reversible bonds (physical bonds), which can be made or broken under certain environments, or covalent bonds. In order to keep the spatial structure of hydrogel, the polymer chains are usually physically or chemically cross-linked [3]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
