Preparation and Characterization of Superporous Hydrogels as pH-Sensitive Drug Delivery System for Pantoprazole Sodium

Abstract

The objective of the present study is to develop Superporous Hydrogel (SPH) and SPH composites (SPHC) as pH-sensitive drug delivery system for Pantaprazole sodium. In this investigation, Superporous hydrogels containing poly(methacrylic acid-co-acrylamide) with interconnected pores of several hundreds of micrometer were prepared using radical polymerization of methacrylic acid and acrylamide in the presence of N,N-methylene-bis-acrylamide as crosslinking agent. A gas blowing method using bicarbonate as a foaming agent was applied to introduce the porous structure. SPH composite polymers were made in the same way, except for using Ac-Di-Sol as a stabilizer. The structures of the SPH and SPH composites were characterized by FT-IR and Scanning electron microscopy (SEM). Apparent density and swelling ratio studies were also carried out. The swelling properties and mechanical strength of SPHs were affected by the addition of the mechanical stabilizer, Ac-Di-Sol. Results indicated that SPH polymers have more pores and higher swelling ratio but less mechanical stability compared to SPH composite polymers, which have less pores and lower swelling ratio but a higher mechanical stability. With a change in pH from acidic to basic, a considerable increase in swelling was observed for all the formulations. Since the prepared SPH and SPHC swell only in the basic pH, it may be concluded that SPH and SPHC can be used as pH-sensitive drug delivery systems for Pantoprazole sodium.

Super Porous Hydrogel: A Promising Gastroretentive Drug Delivery System

“…The dried SPH was allowed to hydrate in excess of deionized distilled water at room temperature .the weight of hydrating sample was measured at time intervals,after excess water was removed by gentle blotting .the swelling ratio was defined as [49,50] …”

“…[57] It absorbed ethanol and swollen, which leaded to blotting of ethanol on the surface. Porosity is calculated from following equation.…”

“…A gastric simulator, based on the water hammer theory, utilizes a controlled amount of different types of stresses on objects immersed in the testing fluid to simulate forces that a sample might receive upon ingestion in body. [61,62] …”

“…[63] The mixture is filtered and drug content is determined using UV-Vis spectrophotometer at appropriate wavelength. [64,65] Fourier transform infrared spectroscopy…”

“…[70] The time required for piece of hydrogel to rise to the surface and float is taken as the floating lag time.Total time period for which tablet or piece of hydrogel remains buoyant is considered as a total floating time. [71] www.wjpps.com Vol 6, Issue 5, 2017. 152…”