Development of Novel Interpenetrating Network Gellan Gum-Poly(vinyl alcohol) Hydrogel Microspheres for the Controlled Release of Carvedilol

Abstract

Novel interpenetrating polymeric network microspheres of gellan gum and poly(vinyl alcohol) were prepared by the emulsion cross-linking method. Carvedilol, an antihypertensive drug, was successfully loaded into these microspheres prepared by changing the experimental variables such as ratio of gellan gum:poly(vinyl alcohol) and extent of cross-linking in order to optimize the process variables on drug encapsulation efficiency, release rates, size, and morphology of the microspheres. Formation of interpenetrating network and the chemical stability of carvedilol after preparing the microspheres was confirmed by Fourier transform infrared spectroscopy. Differential scanning calorimetry and x-ray diffraction studies were made on the drug-loaded microspheres to investigate the crystalline nature of the drug after encapsulation. Results indicated a crystalline dispersion of carvedilol in the polymer matrix. Scanning electron microscopy confirmed the spherical nature and smooth surface morphology of the microspheres produced. Mean particle size of the microspheres as measured by laser light scattering technique ranged between 230 and 346 microm. Carvedilol was successfully encapsulated up to 87% in the polymeric matrices. In vitro release studies were performed in the simulated gastric fluid or simulated intestinal fluid. The release of carvedilol was continued up to 12 h. Dynamic swelling studies were performed in the simulated gastric fluid or simulated intestinal fluid, and diffusion coefficients were calculated by considering the spherical geometry of the matrices. The release data were fitted to an empirical relation to estimate the transport parameters. The mechanical properties of interpenetrating polymeric networks prepared were investigated. Network parameters such as molar mass between cross-links and cross-linking density for interpenetrating polymeric networks were calculated.

Polymeric blend microspheres for controlled release of theophylline

“…23,26 The percentage of uptake data of the completely swollen (at the attainment of equilibrium sorption) crosslinked microspheres presented in Table I indicate that, as the amount of GA in the matrix is increased from 2 to 8 mL, the % equilibrium uptake decreased significantly from 312 to 260 because of the formation of a more rigid semi-IPN matrix at higher crosslink density (i.e., at higher amount of GA in the matrix). Notice that formulations containing the highest amount of HEC exhibited higher equilibrium uptake (higher swelling) i.e., formulation F9 (40 wt % of HEC) exhibited higher equilibrium uptake than F8 (30 wt % of HEC), F7 (20 wt % of HEC) and F2 (10 wt % of HEC) because of increased hydrophylicity induced by the presence of HEC, which facilitates higher absorption of water compared with PVA.…”

Novel interpenetrating network microspheres of xanthan gum–poly(vinyl alcohol) for the delivery of diclofenac sodium to the intestine—in vitro and in vivo evaluation

“…Earlier, PVA-gellan gum (Agnihotri & Aminabhavi, 2005), PVA-guar gum (Soppimath et al, 2000), and PVA-polyacrylic acid IPN (Kurkuri & Aminabhavi, 2004) microspheres were developed for controlled release of drugs. Although sodium carboxy methyl xanthan gum was used to prepare microparticles (Ray et al, 2008), in the literature of pharmaceutics we are not aware of preparation of microspheres from IPN of XG, which can be safely used in food and cosmetics without any specific quantity limitations (Katzbauer, 1998) and PVA for the controlled release of DS.…”

Gellan Gum‐based Hydrogels for Tissue Engineering Applications

“…Another important area of application of the GG derivatives is oral drug delivery [31]. Interestingly, Agniotri et al [32] also reported on interpenetrating networks of GG-poly(vinyl alcohol) hydrogel for producing microspheres aimed at find applications in the controlled release of carvedilol, an antihypertensive drug.…”