Aim:Synthesis of superporous hydrogel with different concentrations of crosslinker was carried out using solution polymerization to study its effect on characteristics of superporous hydrogel. Methylene-bis-acrylamide was used as a crosslinker.Materials and Methods:The characterization studies were performed by measurement of apparent density, porosity, swelling studies, mechanical strength studies, and scanning electron microscopy analysis. Results and Discussion: As the concentration of crosslinker increased from 7.37% to 14.36 % the porosities decreased. In double distilled water, superporous hydrogels showed good increase in equilibrium swelling capacity compared to that in simulated gastric fluid. Scanning electron microscopic images clearly indicated the formation of interconnected pore and capillary channels. Characterization studies revealed that the increase in crosslinker concentration is beneficial from the mechanical stability point of view, but at the same time the decrease in porosity may lead to decrease in drug release rate by diffusion through these capillary channels. Batches B1 and B2 with low concentrations of crosslinker provide good porous structure, swelling characteristics, and mechanical strength appropriate for further applications of superporous hydrogel-based drug delivery systems.Conclusion:The concentration of crosslinker affects the porous structure, swelling characteristics and mechanical strength. By setting appropriate degree of crosslinking it is possible to prepare superporous hydrogel having desired characteristics, which will provide a platform to design the drug delivery systems based on it.

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Introduction:Superporous hydrogel (SPH) swells very rapidly in a shorter period of time to an equilibrium size and contains highly porous structure.Aim:The synthesis of SPH of poly (acrylamide-co-acrylic acid) and its composites viz. Ac-Di-Sol and polyvinylpyrollidone (PVP) was carried out by solution polymerization.Materials and Methods:The SPH and SPH composites (SPHCs) were characterized by measurement of apparent density, porosity, swelling, mechanical strength, and scanning electron microscopy (SEM) studies.Results:FTIR studies confirmed the existence of acrylamide and acrylic acid in SPH. In distilled water SPH showed tremendous increase in equilibrium swelling capacity with conventional SPH as compared to its SPHCs of Ac-Di-Sol and PVP due to the increased in physical cross-linking network, respectively. The presence of Ac-Di-Sol and PVP in SPHCs increased the mechanical strength as compared to conventional SPH which is suitable for gastric retention. SEM pictures clearly indicated the formation of interconnected pores and capillary channels.Conclusion:The amount and type of polymers used affect almost all the characterization parameters of SPHs, and hence, depending upon the applications perspective such polymers could be used in drug delivery systems, successfully.

Objective:In this study efforts have been made to design a drug delivery system based on a superporous hydrogel composite, for floating and sustained delivery of Ranitidine hydrochloride.Materials and Methods:The characterization studies were performed by the measurement of apparent density, porosity, swelling studies, mechanical strength studies, and scanning electron microscopy studies. The prepared formulation was evaluated for buoyant behavior, in vitro drug release, kinetics of drug release, and stability. The release profile of Ranitidine hydrochloride was investigated by changing the release retardant polymer in the formulation. To ascertain the kinetics of drug release, the drug release profiles were fitted to mathematical models that included zero-order, first-order, Higuchi, Hixson-Crowell, Korsmeyer-Peppas, Weibull, and Hopfenberg models.Results:Scanning electron microscopy images clearly indicated the formation of interconnected pores and capillary channels, and cross-linked Chitosan molecules were observed around the peripheries of the pores. The prepared drug delivery system floated and delivered the Ranitidine hydrochloride for about 17 hours. The in vitro drug release from the proposed system was best explained by the Korsmeyer-Peppas model. The values of the diffusion exponent in the Korsmeyer-Peppas model ranged between 0.47 ± 0.02 and 0.66 ± 0.02, which appeared to indicate a coupling of the diffusion and erosion mechanisms, anomalous non-Fickian transport.Conclusion:It was concluded that the proposed floating drug delivery system, based on the superporous hydrogel composite containing Chitosan as a composite material, is promising for stomach-specific delivery of Ranitidine hydrochloride.

In the present investigation an attempt was made to enhance the solubility and dissolution of poorly soluble drug, isotretinoin, by formulating self-nanoemulsifying drug delivery system (SNEDDS). Liquid SNEDDSs were prepared using Transcutol P as oil, Tween 80 as surfactant, and PEG 400 as cosurfactant. Pseudoternary phase diagrams were constructed to identify the efficient self-nanoemulsification region. The formulation with 40% oil (Transcutol P) and 60% surfactant: cosurfactant (Tween 80: PEG 400) ratio of 1 : 1 was optimized based on evaluation parameters for droplet size analysis, self-emulsification capacity, zeta potential, andin vitrodrug release performance. The optimized system contains mean droplet size of 36.60 nm and zeta potential (ζ) −26.73 mV. The optimized formulation A1 was adsorbed onto Fujicalin to produce solid SNEDDS, which exhibited good flow properties and preserved the self-emulsification properties of liquid SNEDDS. The differential scanning calorimetry, FT-IR studies of solid SNEDDS revealed transformation of isotretinoin into molecularly dissolved state in the liquid SNEDDS.In vitrodissolution profiles showed that dissolution rate of ISN from solid SNEDDS was significantly greater as compared to pure drug.