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Preeti K Suresh*,Satish K Suryawani,Divya Dewangan
Pharmacie Globale : International Journal of Comprehensive Pharmacy , 2011,
Abstract: Multicomponent drug delivery systems have found several potential diagnostic and therapeutic applications. Among these the interpenetrating polymeric network (IPN) has emerged as one of the most useful novel biomaterial, which is entanglement of polymer networks with at least one network synthesized and/or cross-linked in the presence of the other. The development of IPN is attractive because they provide free volume space for the easy encapsulation of drugs in the three-dimensional network structure which are obtained by cross-linking of two or more polymer network. This review focuses on the IPN hydrogels based on chitosan for oral drug delivery applications. Chitosan is a natural, biodegradable, nontoxic, mucoadhesive and biocompatible polymer and has found diverse pharmaceutical applications. Chitosan based IPN hydrogels have garnered immense attention as a vehicle for oral drug delivery. The suitability of chitosan based IPN hydrogels as potential oral delivery vehicle stems from their capability of imbibing large amount of body fluid without solubilisation and potential for encapsulation of large amount of drugs, adaptability to be combined with specific responsive polymer(s). This review also summarizes IPN and various multicomponent polymeric materials for developing drug delivery vehicle.
Interpenetrating polymeric network hydrogel for stomach-specific drug delivery of clarithromycin: Preparation and evaluation  [cached]
Gupta Anish,Siddiqui Abdul,Datta Maurya,Ramchand Dhakar
Asian Journal of Pharmaceutics , 2010,
Abstract: The aim of this study was to develop a controlled release system targeting antibiotic delivery to the stomach. The hydrogels were synthesized by using chitosan, poly (acrylic acid) and poly (vinyl pyrrolidone) polymers crosslinked with glutaraldehyde and N,N′-methylenebisacrylamide. Interpenetrating polymeric network (IPN) hydrogels were prepared by varying the concentration of crosslinking agent (glutaraldehyde). The amount of chitosan, poly (acrylic acid), poly (vinyl pyrrolidone) and N,N′-methylenebisacrylamide were kept constant in all formulations. The effect of glutaraldehyde concentration on the swelling and release characteristics were evaluated. Modalities used to assess the most optimal hydrogel formulation included high liquid chromatography, FTIR analysis, differential scanning calorimetry, swelling studies, in vitro drug release study, mucoadhesive study and scanning electron microscopy. The result showed that IPN hydrogels were greater in swelling, more mucoadhesive and released more drug at lower pH values. Thus, it is believed that the antibiotic concentration in the stomach might be sustained through this formulation.
Manjusha Rani,Anuja Agarwal,Yuvraj Singh Negi
BioResources , 2010,
Abstract: Chitosan obtained by alkaline deacetylation of chitin is a non-toxic, biocompatible, and biodegradable natural polymer. Chitosan-based hydrogel polymeric beads have been extensively studied as micro- or nano-particulate carriers in the pharmaceutical and medical fields, where they have shown promise for drug delivery as a result of their controlled and sustained release properties, as well as biocompatibility with tissue and cells. To introduce desired properties and enlarge the scope of the potential applications of chitosan, graft copolymerization with natural or synthetic polymers on it has been carried out, and also, various chitosan derivatives have been utilized to form beads. The desired kinetics, duration, and rate of drug release up to therapeutical level from polymeric beads are limited by specific conditions such as beads material and their composition, bead preparation method, amount of drug loading, drug solubility, and drug polymer interaction. The present review summarizes most of the available reports about compositional and structural effects of chitosan-based hydrogel polymeric beads on swelling, drug loading, and releasing properties. From the studies reviewed it is concluded that chitosan-based hydrogel polymeric beads are promising drug delivery systems.
Development and Evaluation of a New Interpenetrating Network Bead of Sodium Carboxymethyl Xanthan and Sodium Alginate  [PDF]
Rajat Ray, Siddhartha Maity, Sanchita Mandal, Tapan K. Chatterjee, Biswanath Sa
Pharmacology & Pharmacy (PP) , 2010, DOI: 10.4236/pp.2010.11002
Abstract: Interpenetrating network (IPN) beads of sodium carboxymethyl xanthan (SCMX) and sodium alginate (SAL) were pre-pared by ionotropic gelation process using AlCl3 as a cross-linking agent. The effect of different formulation vari-ables like total polymer concentration, gelation time, concentration of cross-linking agent, and drug load on the extent of release of ibuprofen (IBP), a non steroidal anti-inflammatory drug, was examined. The formation of IPN structure was examined using Fourier Transform Infra-red (FTIR) analysis and the compatibility of the drug in the bead was evaluated through FTIR, X-ray diffraction (XRD) and Differential Scanning Calorimetry (DSC) analyses. While increase in the concentration of total polymer, gelation time, and drug load decreased the drug release in both acidic (pH-1.2) and phosphate buffer (PB) solution (pH-6.8), increase in the concentration of cross-linking agent tended to increase the drug release. However, from all the formulations, the drug release in acidic medium was considerably slow and a maximum 14% of the loaded drug was released in 2 h. Complete drug release was achieved in PB solution within 210 to 330 min depending upon the formulation variables. The release of the drug followed non-Fickian transport process in acidic medium and case-II transport mechanism in PB solution and these release behaviour correlated well with the kinetics of dynamic swelling of IPN beads. The study indicated that the IPN beads of SCMX and SAL could be a suitable dosage form to minimize the drug release in acidic solution and to control the drug release in PB solution depending upon the need.
The Influence Factors Analysis to Improve the Compatibility and the Mechanical Behavior of IPN, Gradient IPN and BaTiO3 Filled IPN  [PDF]
Yudi Guo, Dongyan Tang, Ying Wang
Materials Sciences and Applications (MSA) , 2012, DOI: 10.4236/msa.2012.39087
Abstract: Interpenetrating polymer network (IPN), gradient IPN and BaTiO3 filled IPN, composed of poly(ethylene glycol urethane) (PEGPU) and unsaturated polyester resin (UP) curing at room temperatures were prepared. Then the effect of soft/hard segment ratio in polyurethane (PU), component ratio of PU to UP in IPN, adding amount of BaTiO3 in filled IPN, the component sequences and interval times between each IPN for gradient IPN, on morphology and mechanical behavior of IPN and BaTiO3/IPN nanocomposites with different molecular weight of PU were studied systematically. Moreover, the investigation on the relationship between the morphologies and the mechanical properties indicated that the IPN with finer morphology exhibited an excellent consistency of the higher strengths and elongations.
Simultaneous and Gradient IPN of Polyurethane/Vinyl Ester Resin: Morphology and Mechanical Properties  [PDF]
Dongyan Tang,Xiaohong Zhang,Lili Liu,Liangsheng Qiang
Journal of Nanomaterials , 2009, DOI: 10.1155/2009/514124
Abstract: A series of polyurethane (PU) and vinyl ester resin (VER) simultaneous and gradient interpenetrating polymer networks (represented as s-IPN and g-IPN, resp.) curing at room temperature were prepared by changing the component ratios of PU or VER in s-IPN, time intervals, and component ratio sequences of s-IPN in g-IPN. The microstructures of s-IPN and g-IPN were detected by atomic force microscope (AFM), dynamic mechanical analyzer (DMA), and surface constitution scanning of nitrogen element of energy dispersive X-ray spectrum (EDX), respectively. The mechanical properties of s-IPN and g-IPN were studied by values in strain-stress curves detected by electronic multipurpose tester. The results indicated that the morphology and mechanical properties are both affected by PU/VER component ratios in s-IPN, gradient time intervals, and gradient component ratio sequences. Furthermore, the morphology detection by EDX and mechanical properties study both proved the formation of gradient structures in transition regions of g-IPN.

YU Xue-hai,CHEN Qi-ming,GENG Kui-shi,YAN Jin-qiang,WANG Yuan-shen,

高分子学报 , 1989,
Abstract: A new series of interpenetrating polymer network based on castor oil, toluene diisocyanate and hydroxyethyl methacrylate (HEMA) (Network I) and castor oil, TDI and polypropylene glycol (PPG) (Network II) was prepared. Their structure and properties were studied by solid NMR and dynamic mechanical analysis. Mechanical and dynamic mechanical measurements show that the tensile properties increase and tan 6 peaks broaden. Solid NMR results indicate that the interface ratio increase but it does not vary with relative amount of network I and network II whtch reveals that the samples might exhibit a core-shell structure.
Preparation and characterization of gelatin-poly(methacrylic acid) interpenetrating polymeric network hydrogels as a ph-sensitive delivery system for glipizide  [cached]
Gupta N,Satish C,Shivakumar H
Indian Journal of Pharmaceutical Sciences , 2007,
Abstract: In the present study, interpenetrating polymeric network hydrogels of glipizide were prepared using gelatin and methacrylic acid. Methacrylic acid was polymerized using potassium persulfate. Methacrylic acid was crosslinked with methylene bisacrylamide and gelatin was crosslinked using glutaraldehyde. Four formulations were prepared by varying the concentrations of methacrylic acid, methylene bisacrylamide and glutaraldehyde. The amounts of gelatin and potassium persulfate were kept constant in all the formulations. The interpenetrating polymeric network hydrogels were characterized by fourier transform infrared analysis, differential scanning calorimetry and evaluated for swelling and deswelling properties, drug loading and in vitro drug release. All the formulations showed no interaction between drug and polymer as confirmed by fourier transform infrared analysis and differential scanning calorimetric studies. The interpenetrating polymeric network hydrogels swelled only in alkaline pH and swelling was minimal in acidic pH. It was found that as the concentration of cross-linking agents is increased, there is a decrease in swelling and, as the concentration of methacrylic acid is increased, there is an increase in swelling. The release data shows that, as the concentration of methacrylic acid was increased, swelling increased resulting in increased release of the drug.
Interfacial Actions and Adherence of an Interpenetrating Polymer Network Thin Film on Aluminum Substrate  [PDF]
Weiwei Cui, Dongyan Tang, Jie Liu, Fan Yang
Journal of Surface Engineered Materials and Advanced Technology (JSEMAT) , 2011, DOI: 10.4236/jsemat.2011.13013
Abstract: The interpenetrating polymer networks (IPN) thin film with the –C=O group in one network and the terminal –N=C=O group in another network on an aluminum substrate to reinforce the adherence between IPN and aluminum through interfacial reactions, were obtained by dip-pulling the pretreated aluminum substrate into the viscous-controlled IPN precursors and by the following thinning treatment to the IPN film to a suitable thickness. The interfacial actions and the adhesion strengths of the IPN on the pretreated aluminum substrate were investigated by the X-ray photoelectron spectroscopy (XPS), Fourier transform infrared spectroscopy (FTIR) and strain-stress(?-?) measurements. The XPS and FTIR detection results indicated that the elements’ contents of N, O, and Al varied from the depths of IPN. The in-terfacial reaction occurred between the –N=C=O group of IPN and the AlO(OH) of pretreated aluminum. The in-creased force constant for –C=O double bond and the lower frequency shift of –C=O stretching vibration absorption peak both verified the formation of hydrogen bond between the –OH group in AlO(OH) and the –C=O group in IPN. The adherence detections indicated that the larger amount of –N=C=O group in the IPN, the higher shear strengths between the IPN thin film and the aluminum substrate.
Formulation and In Vitro evaluation of pH sensitive oil entrapped polymeric blended gellan gum buoyant beads of clarithromycin
G Tripathi,S Singh
DARU : Journal of Pharmaceutical Sciences , 2010,
Abstract: "n "nBackground and the purpose of the study: A gastroretentive pH sensitive system has been a frontier approach to release the drug in controlled manner in stomach and duodenum. The aim of this study was to develop buoyant beads of gellan based, wherein, the oil was entrapped, blended with hydroxypropyl methyl cellulose or carbopol 934 in order to evaluate its potential for targeted sustained delivery of clarithromycin in the gastric region. "nMethods: Buoyant beads of gellan was developed by inotropic gelation technique using calcium carbonate as gas forming agent and the drug polymer dispersion was emulsified with mineral oil. The oil was entrapped and blended with hydroxypropyl methyl cellulose or carbopol 934. The developed beads were evaluated in terms of diameter, % floating, encapsulation efficiency, In vitro drug release, In vivo gastric residence efficacy and clarithromycine concentration in the mucosa of the experimental animal model. "nResults: The scanning electron microscope photograph indicated that the prepared beads were spherical in shape and buoyancy, encapsulation efficiency and drug content obtained from all batches were satisfactory. Particle size and percentage buoyancy of the gel beads increased by raising the concentration of calcium carbonate. The formulation exhibited sustained release profile and was best fitted in the Peppas model with n < 0.45. Subsequent coating of microbeads exhibited zero-order sustained pattern of the drug release up to 8 hrs. Batch B4 showed comparatively better residence and the drug concentration in the gastric mucosa of the treated animals. Conclusion:The result provides evidence that the prepared optimized formulation may be used effectively for pH sensitive gastric targeted antibiotic such as clarithromycin.
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