Intelligent hydrogels are a new class of material which has recently attracted great interest for biomedical applications. This kind of hydrogels are very sensitive to environmental stimulus, which manifested by a sharp phase transition. Stimuli-responsive (smart) hydrogels have attracted widespread attention as biomimetic systems due to their ability to respond to changes in external and internal stimuli ranging from physical triggers such as temperature and electric field to chemical triggers like glucose and pH, a feature which is important for their application particularly in pharmaceutical field. The aim of this work was to prepare a series of intelligent nanocomposite hydrogels based on poly(vinyl alcohol) (PVA) and ethylene glycol dimethylacrylate (EGDMA) as crosslinker and silica nanoparticles demonstrating pH-dependant swelling behavior. Herein, the nanocomposite hydrogels were prepared via radical polymerization in the presecnce of different concentrations of EDGMA (10%, 20% and 30%), and their structure was characterized by Fourier-transform infrared spectroscopy (FTIR) spectroscopy. The effect of EDGMA concentration on the swelling properties and gel content of samples were also investigated. The obtained results revealed that all of the samples showed maximum swelling in acidic pH. The developed smart hydrogels in the current study have a high potential for drug delivery system.
