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In the present study, main complication associated with duodenal ulcer is bleeding that was due to frequent use of NSAIDs, which was treated by ranitidine HCL (RNT). For the targeted release of RNT, pH-sensitive gelatin/acrylamide networks were synthesized by free radical polymerization, and the effect of different concentrations of initiator, monomer, polymer, and cross-linker on swelling was observed. Average molecular weight (Mc), volume fraction of the polymer V2, solvent interaction parameter, and cross-linked density were calculated. FTIR and SEM studies were performed for the interaction and morphological studies of networks. Dissolution efficiency (DE) and percentage release of RNT were analyzed in acidic media as well as in alkaline phosphate buffer pH 7.5. 80% swelling in phosphate buffer of pH 7.5 in 12 h showed inverse behavior with the concentration of cross-linker and direct relation with the gelatin. Akaike information criteria (AIC) were used for the selection of one best model. Formulation AAm1Ge1 at pH 7.5 has the best fitting curve with maximum regression coefficient 0.94 and minimum 66 AIC values. 80% RNT release with non-Fickian behavior and was observed in all prepared networks. Proposed networks formulations can be used for the treatment of NSAIDs induced duodenal ulcer.

Th accurate rapid, simple and selective reversed phase high performance liquid chromatography (RP-HPLC) has been established and validated for the determination of captopril (CAP). Chromatographic separation was accomplished using prepacked ODSI C18 column (250 mm × 4.6 mm with 5 μm particle size) in isocratic mode, with mobile phase consisting of water: acetonitrile (60:40 v/v), pH adjusted to 2.5 by using 85% orthophosphoric acid at a flow rate of 1 mL/min and UV detection was performed at 203 nm. RP-HPLC method used for the analysis of CAP in mobile phase and rabbit plasma was established and validated as per ICH-guidelines. It was carried out on a well-defined chromatographic peak of CAP was established with a retention time of 4.9 min and tailing factor of 1.871. The liquid–liquid extraction method was used for extraction of CAP from the plasma. Excellent linearity (R2 = 0.999) was shown over range 3.125–100 µg/mL with mean percentage recoveries ranges from 97 to 100.6%. Parameters of precision and accuracy of the developed method meet the established criteria. Intra and inter-day precision (% relative standard deviation) study was also performed which was less than 2% which indicate good reproducibility of the method. The limit of detection (LOD) and quantification for the CAP in plasma were 3.10 and 9.13 ng/mL respectively. The method was suitably validated and successfully applied to the determination of CAP in rabbit plasma samples.

Enteric coating of hydrogel beads is an effective approach to resolve the drug entrapment problem reported in previous studies. In the present study, microencapsulation of drug in hydrogel beads with extrusion-dripping technique was used for the improvement of the drug entrapment efficiency. Calcium chloride dehydrate was used as a cross-linking agent and oil-in-oil solution of eudragit S-100 was used as coating material while diclofenac sodium was used as a model drug. Optical microscopy, scanning electron microscopy, weight, elemental, and size variation of prepared hydrogels beads were analyzed and found within the acceptable limits. The drug loading and release studies of the coated beads were evaluated. Retardation of the model drug in gastric and intestinal pH environment until 8 h was observed which made the prepared hydrogels more targeted and colon-specific. In acidic pH 1.2, negligible percentage release was observed, whereas at pH 7.4, 98% diclofenac sodium was estimated after 8 h. In vitro release, kinetic studies proved that concentration-dependent release behavior of diclofenac sodium followed Fick’s law of diffusion in coated form, while non-Fickian behavior was observed in uncoated beads. Prepared hydrogel beads may be used as a promising tool for sustained release of drug targeting colon.

The aim of present research aims to fabricate a system of enteric coating of hydrogel beads with pH-sensitive polymer, which shows solubility at pH > 7, and explore their potential to target the colon for drug delivery. Hydrogel beads were fabricated through the extrusion-dripping technique followed by ion gelation crosslinking. Moreover, freeze-thaw cycle was implemented for crosslinking of polyvinyl alcohol (PVA)/Ca-alginate blend beads. The oil-in-oil solvent evaporation method was adopted for the Eudragit coating of hydrogel beads using different coat: core ratios (4:1 or 8:1). Coated and uncoated hydrogel beads were evaluated by in vitro physicochemical properties, swelling and drug release behaviours, and in vivo pharmacokinetics, swelling, and toxicity evaluation. Diclofenac sodium was loaded as an experimental drug. Drug entrapment efficiency for the PVA/Ca-alginate beads was calculated as 98%, and for Ca-alginate beads, it came out to a maximum of 74%. Drug release study at various pH suggested that, unlike uncoated hydrogel beads, the coated beads delay the release of diclofenac sodium in low pH of the gastric and intestinal environment, thus targeting the colon for the drug release. It was concluded that Eudragit S-100-coated hydrogel beads could serve as a more promising and reliable way to target the colon for drug delivery. Graphical abstract

The aim of this work was the development and evaluation of controlled release formulations consisting of methacrylate derivatives and ethyl cellulose synthesized using oil-in-oil solvent evaporation method. Drug release studies were performed in different dissolution media. Maximum drug released was observed at pH 7.4. Fourier transform infrared spectroscopy spectra, SEM and thermal analysis showed compatibility between drug and polymers. Pharmacokinetic parameters were calculated by Phoenix WinNonlin® version 6.3 software. The average AUC0–t was found to be 2483.71 ± 13.173 ng/ml h, 5954.37 ± 12.110 ng/ml h, 6400.82 ± 19.131 ng/ml h and 7427.4 ± 49.322 ng/ml h for group 1–4, respectively. The maximum concentration (Cmax) of IBH for all groups predicted from pharmacokinetics data was 880.38 ng/ml, 718.43 ng/ml, 721.87 ng/ml and 805.11 ng/ml, respectively. Thus, in vitro and in vivo drug release studies of polymeric microspheres proved their controlled release behavior with preferential delivery for an extended period of time.

Introduction: The current work was aimed to design and synthesize novel crosslinked pH-sensitive gelatin/pectin (Ge/Pec) hydrogels using different polymeric ratios and to explore the effect of polymers and degree of crosslinking on dynamic, equilibrium swelling and in vitro release behavior of the model drug (Mannitol). Methods: The Ge/Pec based hydrogels were prepared using glutaraldehyde as the crosslinker. Various structural parameters that affect their release behavior were determined, including swelling study, porosity, sol-gel analysis, average molecular weight between crosslinks (Mc), volume fraction of polymer (V2,s), solvent interaction parameter (χ) and diffusion coefficient. The synthesized hydrogels were subjected to various characterization tools like Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD) and DSC differential scanning calorimetry (DSC) and scanning electron microscopy (SEM). Results: The hydrogels show highest water uptake and release at lower pH values. The FTIR spectra showed an interaction between Ge and Pec, and the drug-loaded samples also showed the drug-related peaks, indicating proper loading of the drug. DSC and TGA studies confirmed the thermal stability of hydrogel samples, while SEM showed the porous nature of hydrogels. The drug release followed non-Fickian diffusion or anomalous mechanism. Conclusion: Aforementioned characterizations reveal the successful formation of copolymer hydrogels. The pH-sensitive swelling ability and drug release behavior suggest that the rate of polymer chain relaxation and drug diffusion from these hydrogels are comparable which also predicts their possible use for site-specific drug delivery.

In the present study chitosan derivative, O-carboxymethylated chitosan (O-CMC) was synthesized by simple and cost-effective technique and scrutinized for in-vivo anti-inflammatory and analgesic activities. Na-carboxymethyl intermediate was prepared by acidification of chitosan with monochloroacetic acid and neutralized with 0.5 M NaOH which was further converted into O-CMC by using 0.2 M HCl. Resulted O-CMC was confirmed by FTIR spectroscopy. Inflammation was induced in albino rats by carrageenan and anti-inflammatory property of synthesized O-CMC was confirmed by calculating paw volume, %age inflammation and %age inhibition of inflammation. Analgesic properties were confirmed by %age analgesia and latency time. The results revealed that the synthesized O-CMC derivative of chitosan showed stretched peaks at 2891 cm−1, 1631 cm−1, 1060 cm−1 of -OH, -NH and -CO respectively. Formulation V was optimized due to its of percentage inflammation, 45.5 ± 0.02% inhibition of inflammation and decrease in paw volume, as well as a positive control on % age analgesia and latency time as compared to chitosan by applying statistics. O-CMC may be considered a remarkable anti-inflammatory and analgesic agent which may provide adjunctive effect with other active pharmaceutical ingredients.

Objective of the study was to perform a physico-chemical modification of low molecular weight chitosan (CTS) followed by its use in the formulation of nanoparticles carrier of Acyclovir (ACY). Modified polymer was used to develop ACY loaded nanoparticles in order to achieve optimal response and to minimize toxic effects of ACY. CTS were dissolved in varying concentrations of potassium hydroxide solution to synthesize N, O-carboxymethylated chitosan (N,O-CMC). Synthesized derivative was further processed with different concentrations of TPP (0.3%, 0.5% and 1%) and ACY to prepare nanoparticles. N,O-CMC and prepared formulations were characterized by Fourier transform infrared spectroscopy (FTIR). Furthermore, scanning electron microscopy (SEM) was done to observe the surface morphology, zeta size and zeta potential for particle size analysis, in vitro dissolution to find out the release pattern and kinetic modeling was done to observe the release mechanism and pattern of the drug. Result of FTIR was evidence of polymer modification when compared with chitosan which was the parent standard polymer as well as compatibility of the ingredients. Results of zeta size analysis have confirmed that the particles are of nanosized (109-125nm). Good controlled 98.77% over release of 24 h of formulation B observed in phosphate buffer of intestinal pH. Higuchi model with Fickian diffusion was dominating due to the formation of N, O-CMC complex which created smooth surface. All the results were significant and within the p value of 0.001. Conclusively, the modification of the CTS was in nanoparticle showed good sustained release.

In present investigation new formulations of Sodium Alginate/Acrylic acid hydrogels with high porous structure were synthesized by free radical polymerization technique for the controlled drug delivery of analgesic agent to colon. Many structural parameters like molecular weight between crosslinks (M c), crosslink density (M r), volume interaction parameter (v 2,s), Flory Huggins water interaction parameter and diffusion coefficient (Q) were calculated. Water uptake studies was conducted in different USP phosphate buffer solutions. All samples showed higher swelling ratio with increasing pH values because of ionization of carboxylic groups at higher pH values. Porosity and gel fraction of all the samples were calculated. New selected samples were loaded with the model drug (diclofenac potassium).The amount of drug loaded and released was determined and it was found that all the samples showed higher release of drug at higher pH values. Release of diclofenac potassium was found to be dependent on the ratio of sodium alginate/acrylic acid, EGDMA and pH of the medium. Experimental data was fitted to various model equations and corresponding parameters were calculated to study the release mechanism. The Structural, Morphological and Thermal Properties of interpenetrating hydrogels were studied by FTIR, XRD, DSC, and SEM.

In this study, microspheres of Eudragit FS30D and ethyl cellulose (EC) were prepared by oil-in-oil (O/O) solvent evaporation method with the addition of 1% span 80 as emulsifier. Ivabradine HCl (IBH) was encapsulated into microspheres by the in situ method. The resultant microspheres were characterized with respect to drug loading, Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), X-ray diffractometry (XRD), differential scanning calorimetry (DSC), and release behavior. Chemical stability of IBH encapsulated into prepared microspheres was confirmed by FTIR, DSC, and XRD analysis. SEM images showed spherical microspheres. Maximum percentage entrapment efficiency of ivabradine was found to be 45.1% and percentage yield was about 71.66%. Maximum in vitro drug release was 95.9% for the pH 7.5 buffer solution which demonstrated the pH sensitivity of microspheres. Cumulative drug release data were analyzed using different kinetic models. Korsmeyer–Peppas equation was used to determine the value of n which follows non-Fickian diffusion.

In this study, a series of pH sensitive microgels (MGs) were prepared by modified free radical suspension polymerization of 2-hydroxyethyl methacrylate (HEMA) and itaconic acid (IA), using ethylene glycol dimethacrylate (EGDMA) as crosslinker. Equilibrium swelling technique was employed for esomeprazole magnesium trihydrate (EMT) loading. Prepared microgels were characterized through Fourier transforms infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), dynamic light scattering technique (DLS), scanning electron microscopy (SEM), equilibrium swelling and in vitro drug release kinetics. FTIR and TGA confirmed the formation of copolymeric p(HEMA-co-IA) network. SEM and DLS revealed smooth, round and uniformly distributed microspheres with particle size up to 10 μm. Developed microgels found to be pH responsive in nature. All the formulations (HIDI - HID5) followed Higuchi model with non-Fickian diffusion mechanism of drug release. It was concluded that p(HEMA-co-IA) microgels have potential to be used as drug carriers for site specific and controlled drug delivery.

A simple, efficient, accurate and selective HPLC method has been developed and validated successfully for the estimation of 5-fluorouracil in rabbit plasma. The drug was eluted by using Supelco C18 column (1.5 cm x 4.6 mm, 5 μm) with a mobile phase consisting of methanol and water (20: 80, v/v) by adjusting pH at 3.2, using perchloric acid solution. The retention time was found to be 4.107 with a flow rate of I mL/min. Multiple validation parameters evaluated with high accuracy indicating that the current method sufficiently qualifies the recommended criteria. Regression value obtained from linearity curve was R² = 0.999 and percentage recovery obtained was ranged from 96.6 to 102.5%. A fine response in short run time with perfect resolution made the method highly suitable for pharmacokinetic studies.

The present study focused to develop rapid, accurate and sensitive reversed-phase high pressure liquid chromatography method for the quantification of esomeprazole (ESO) magnesium in rabbit plasma. Chromatographic separation was achieved isocratically on a reversed-phase C,, column using simple mobile phase consisting of of methanol : acetonitrile: 0.05 M phosphate buffer, pH 7 adjusted with potassium hydroxide (45 : 10 : 45, v/v/v) at a flow rate of 1.0 mL/min and UV detection at 302 nm. The method was validated for system suitability, linearity, precision, accuracy, stability, robustness, LOD and LOQ. The described method stated good linearity over the range of 0.01 to 2.5 pg/mL (r = 0.999). The extraction recovery of esomeprazole was more than 95.3%. The method was precise with relative standard deviation1% with more than 90% accuracy and limit of quantification 0.0309 μg/mL. The freeze thaw stability studies indicated that the rabbit plasma samples containing esomeprazole could be stored in freezer at -20⁰C and handled under normal laboratory conditions without significant loss of drug. In conclusion, the developed method is simple, cost effective and reproducible, with improved sensitivity and running time of analysis.

The objective of this study was to prepare and evaluate ivabradine HCl-loaded microspheres consisting of Eudragit LIOO-55 and ethyl cellulose prepared by oil-in-oil solvent evaporation method. Ivabradine HCl was encapsulated into microspheres by in situ method. The resultant microspheres were characterized with respect to drug loading, flow properties, Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), X-ray diffractometry (XRD), thermal analysis and release behavior. Chemical stability of IBH after being encapsulated into microspheres was confirmed by FTR, DSC and XRD. FTIR spectra reflect- ed no interaction between drug and excipients. TGA indicates that prepared microspheres showed much better thermal stability than pure drug ivabradine. SEM images showed formulation of microspheres in spherical shape. The maximum perceniage entrapment efficiency was found to be 81 ± 2.15 and percentage yield was 88 ± 2.65. The maximum in vito drug release was 94.5% for the pH 7.4 and demonstrated that all drug-loaded formulations had a pH-dependent drug release. The cumulative drug release data were analyzed by applying different kinetic models. Korsmeyer-Peppas equation was used to determine value of n which follows non-Fickian diffusion.

Dendrimers are the valuable additives in different routes of drug administration and are the most successful agents, because dendrimers provide greater biocompatibility, water solubility and bioavailability. In this review, synthesis structures, method of preparation have been discussed. Interaction mechanisms between dendrimer molecules and active pharmaceutical ingredient (API), like simple encapsulation and covalent conjugation and the recent applications of dendrimers have also been focused. Divergent method of poly amidoamine (PAMAM) dendrimers is found to be more applicable as compare to convergent method and PAMAM are also considered as ideal carriers for drug delivery because of large variety of surface groups, high aqueous solubility, and their unique architecture.

Water insoluble drugs with a short plasma half-life face the pharmacokinetic (PK) barriers of low oral absorption from the gastrointestinal route of drug administration and rapid clearance from systemic circulation. We report the synthesis and pharmaceutical profiling of a hybrid dosage form consisting of hydrophilic polymer encapsulated nanoparticles (NPs) of a hydrophobic drug, compressed inside tablets and optimized for efficient PK oral delivery. Four different polymers, i.e. hydroxypropylmethyl cellulose, Na-alginate, pectin and polyvinylpyrrolidone were used separately to nano-encapsulate (700 nm to 1 μm diameter) lornoxicam, a model hydrophobic drug with a short PK half-life, by a solvent emulsification method. The prepared NPs were compressed directly into tablets. The PK study in rats revealed improved oral bioavailability and better PK parameters of the drug after the oral administration of NPs carrying (NC) tablets for each polymer. The same was observed for the pharmacological activity in terms of carrageenan-induced inflammation in rat paw. In the in vitro drug release study, the NC tablets provided additional control over drug release by an interaction of the surface polymer of NPs with the tablet's matrix polymer. NPs showed better rheological properties as compared to crystalline drug, enabling efficient flow and processing of NPs in the tableting machine. The NC tablets appeared advantageous compared to conventional crystalline lornoxicam carrying (CL) tablets, conventional market tablets or even nanoparticles alone in terms of the ease of administration, improved drug stability, tunable drug release and enhanced oral bioavailability.

Microparticles are one of the recent controlled release dosage form, compressed in the form of tablets or filled in capsules. In this review different methods of preparations and their effects on physical properties i.e. Size, shape and porosity which can be controlled by ingredients used or process variables and characterization will be discussed. Future dimensions of these dosage forms are numerous when it comes to its application in drug delivery and to overcome issues associated with new drug molecule in drug discovery process.

In this study, we fabricated pH-sensitive polyvinylpyrrolidone/acrylic acid (PVP/AA) hydrogels by a free-radical polymerisation method with variation in the content of monomer, polymer and cross-linking agent. Swelling was performed in USP phosphate buffer solutions of pH 1.2, 5.5, 6.5 and 7.5 with constant ionic strength. Network structure was evaluated by different parameters and FTIR confirmed the formation of cross-linked hydrogels. X-ray crystallography showed molecular dispersion of tramadol HCl. A drug release study was carried out in phosphate buffer solutions of pH 1.2, 5.5 and 7.5 for selected samples. It was observed that swelling and drug release from hydrogels can be modified by changing composition and degree of cross-linking of the hydrogels under investigation. Swelling coefficient was high at higher pH values except for the one containing high PVP content. Drug release increased by increasing the pH of the medium and AA contents in hydrogels while increasing the concentration of cross-linking agent had the opposite effect. Analysis of the drug release mechanism revealed non-Fickian transport of tramadol from the hydrogels. Nesse estudo, preparamos hidrogéis de polivinilpirrolidona/ácido acrílico(PVP/AA), sensíveis ao pH, por meio de método de polimerização de radical livre, com variações no conteúdo de monômero, de polímero e de agente de ligação cruzada. O inchamento foi realizado em soluções tampão fosfato USP pH 1,2, 5,5, 6,5 e 7,5, com força iônica constante. A estrutura reticular foi avaliada por diferentes parâmetros e o FTIR confirmou a formação de hidrogéis de ligação cruzada. A cristalografia de raios X mostrou dispersão molecular do cloridrato de tramadol. Realizou-se estudo de liberação do fármaco em soluções tampão fosfato pH 1,2, 5,5 e 7,5 para amostras selecionadas. Observou-se que o inchamento e a liberação do fármaco dos hidrogéis podem ser modificados mudando-se a composição e o grau de ligação cruzada dos hidrogéis em estudo. O coeficiente de inchamento foi alto em pH mais altos, exceto para um deles com alto conteúdo de PVP. A liberação do fármaco aumentou com o aumento do pH do meio e do conteúdo em AA nos hidrogéis, enquanto que o aumento na concentração do agente de ligação cruzada apresentou efeito oposto. A análise do mecanismo de liberação do fármaco revelou transporte não Fickiano do tramadol dos hidrogéis.

In this study, polymeric blend microparticles are prepared with tunable drug releasing behavior, imparted by using poly(e-caprolactone) (PCL) as hydrophobic and hydroxypropyl methylcellulose (HPMC) as hydrophilic biodegradable polymeric constituents. Microparticles were prepared by simple oil in water emulsion-solvent evaporation method and evaluated for their sustained release profile by using nifedipine (half-life is about 2 h) as model drug. Hydrophilic PCL is added to optimize the drug release in simulated aqueous body fluid. Polyvinyl alcohol (PVA), used as emulsifier, was found to improve shape while HPMC increased surface smoothness of microparticles. High encapsulation efficiency was achieved, controllable by HPMC concentration. In vitro dissolution studies in acidic and neutral pH showed sustained release profile for all formulations. Synthesized microparticles, provided control over hydrophobic drug release by changing the proportion of HPMC and PCL in formulation at both acidic and intestinal pH.

Chondroitin sulfate and sodium alginate were incorporated in different ratios to prepare glutaraldehyde (GA) crosslinked microspheres by water-in-oil emulsion crosslinking method for delivery of 5-flurouracil (5-FU) to colon. Chemical interaction, surface morphology, thermal degradability, crystallinity evaluation, elemental analysis and drug release results were computed by using FTIR, SEM, DSC and TGA, PXRD, EXD and dissolution studies at pH 1.2, pH 6.8 and pH 7.4, respectively. Results revealed an acetal ring formation, non-porous surfaces, stability up to 450 degrees C with mass loss of 84.31%, variation in carbon and oxygen contents and targeted release at pH 7.4. Different kinetic models were applied on release studies i.e., zero order, first order, Higuchi and Korsmeyer-Peppas. Higuchi model was declared as best fit model based on r2 value (0.99) and mechanism of release was non-Fickian diffusion. A potential approach for colonic delivery of 5-FU was successfully developed.

In the present study pH-sensitive polyvinylpyrrolidone/acrylic acid (PVP/AA) hydrogels were synthesized by free radical polymerization in the presence of ethylene glycol dimethacrylate (EGDMA) as a cross-linker. For this purpose, different concentrations of PVP, AA and EGDMA were used to synthesize polymeric networks. This study focused on evaluating the effect of the composition on the swelling of hydrogels and release of tramadol hydrochloride at varying pH (1.2, 5.5, 6.5 and 7.5). Gel fraction, porosity and diffusion coefficient were also determined. The hydrogels were characterized using scanning electron microscopy for surface morphology, Fourier transform infrared spectroscopy and X-ray diffraction for studying possible chemical interactions. The hydrogels exhibited a pH-dependent swelling behavior. The degree of swelling, as well as drug release from PVP/AA hydrogel, was significantly increased as pH varied from 1.2 to 7.5. Swelling was increased by increasing the AA content, while a decrease in sw...

Purpose: To prepare chondroitin sulphate–polyvinyl alcohol cross-linked microcapsules (miCAPs) for controlled delivery of 5-flurouracil (5-FU) in cancer patients. Method: Nine different miCAP formulations were prepared using emulsion cross-linking procedure. The formulations were evaluated for their physicochemical properties, complex formation, stability at variable temperatures, safety, as well as drug-loading and drug-release characteristics. The effects of glutaraldehyde (GA), polymer concentration and stirring speed on 5-FU release at various pH were also assessed. Results: One of the miCAP formulations (miCAP-1) was adjudged the most suitable based on its particle size, high drug loading (75.3 %, p = 0.034), and high entrapment efficiency (85.2 %, p = 0.031). Best-fit drug release model was Higuchi model based on regression coefficient value (R2) while drug release mechanism was Fickian. Conclusion: Highly stable, crosslinked, amorphous and drug delivery system has been successfully developed. The delivery system is potentially suitable for acid-sensitive therapeutic moieties and where controlled release is desired. Keywords: Emulsion cross-linking, Colon-specific delivery, 5-Flurouracil, Glutaraldehyde, Kinetic models

Flurbiprofen loaded PCL/PVP blend microspheres were prepared by o/w solvent evaporation method using various concentrations of gelatin as emulsifying agent. Microsphere recovery decreased with a decrease in the concentration of the emulsifier in the dispersion. Encapsulation efficiency and drug loading of microspheres increased with decrease in concentration of emulsifying agent. Hydration rate, encapsulation efficiency and drug loading of microspheres increased with increase in concentration of PVP. Rheological properties showed free flowing nature of microspheres. SEM (Scanning electron microscope) revealed microspheres were discrete, spherical and became porous with decrease in concentration of emulsifying agent but smooth with higher concentration of emulsifying agent. FTIR (Fourier transform infrared spectroscopy) spectra of pure and encapsulated flurbiprofen in all formulation showed no significant difference in characteristic peaks, suggesting stability of flurbiprofen during encapsulation process. X-RD (X-ray powder diffractometry) of pure flurbiprofen shows sharp peaks, which decreases on encapsulation, indicating dispersion at molecular level and hence decrease in the crystallinity of drug in microspheres. Microspheres showed an enteric nature at pH 1.2 and a sustained release pattern at pH 6.8. Rapid drug release was observed in microspheres with higher concentration of PVP (polyvinylpyrrolidone), PVP acts as channeling agent. Formulation with low concentration of emulsifying agent also showed a fast release due to porous structure. Drug release kinetics followed zero order at pH 1.2 while at pH 6.8 Higuchi model was best fitted and was found non fickian.

The objective of this work was to develop new pH-sensitive hydrogels to deliver gastric mucosal irritating drugs to the lower part of the gastrointestinal tract. For this purpose, cross-linked vinyl acetate-co-acrylic acid (VAC-co-AA) hydrogels were synthesized by using N, N, methylene bisacrylamide (MBAAm) as a cross-linking agent. Different ratios of 90:10, 70:30, 50:50, 30:70, and 10:90 of VAC-co-AA were synthesized. All of the compositions were cross-linked using 0.15, 0.30, 0.45, and 0.60 mol percent MBAAm. Swelling and aspirin release were studied for 8 hour period. The drug release data were fitted into various kinetic models like the zero-order, first-order, Higuchi, and Peppas. Hydrogels were characterized by Fourier transform infrared spectroscopy and scanning electron microscopy. In addition to the above, these hydrogels were loaded with 2%, 8% and 14% w/v aspirin solutions, keeping the monomeric composition and degree of cross-linking constant. In conclusion, it can be said that aspirin can be successfully incorporated into cross-linked VAC/AA hydrogels and its swelling and drug release can be modulated by changing the mole fraction of the acid component in the gels.

In the present work crosslinked methyl methacrylate-co-itaconic acid (MMA-co-IA) hydrogels were prepared by free radical copolymerization of methyl methacrylate (MMA) with itaconic acid (IA) using ethylene glycol dimethacrylate (EGDMA) and N, N methylene bisacrylamide (MBAAm) as crosslinkers and benzoyl peroxide as initiator. Prepared hydrogels were investigated for dynamic and equilibrium swelling studies. For swelling behaviour, effect of pH, monomeric compositions, degree of crosslinking and type of crosslinking agent were investigated. Swelling studies were performed in the USP phosphate buffer solutions of varying pH 1.2, 4.5, 5.5, 6.5 and 7.0. Results showed that swelling increased by increasing IA content in hydrogels structure. This may be due to the presence of more carboxylic groups available for ionization. Swelling was decreased with increase in crosslinking ratio owing to tighter hydrogel structure. Hydrogels were characterized by Fourier transform infrared (FTIR), and scanning electron microscope (SEM). Polymer-solvent interaction parameters (χ) of hydrogels were determined by using Flory–Rehner theory of equilibrium swelling values. The analysis of diffusion mechanism from gels using Peppas model showed that all monomeric compositions and degrees of crosslinking followed Fickian diffusion.

Background The present work objective was to prepare and to observe the effect of ethylene glycol dimethacrylate on swelling and on drug release behavior of pH-sensitive acrylic acid–polyvinyl alcohol hydrogel. Methods In the present work, pH sensitive acrylic acid–polyvinyl alcohol hydrogels have been prepared by free radical polymerization technique in the presence of benzoyl peroxide as an initiator. Different crosslinker contents were used to observe its effect on swelling and on drug release. Dynamic and equilibrium swelling studies of prepared hydrogels were investigated in USP phosphate buffer solutions of pH 1.2, 5.5, 6.5 and 7.5 with constant ionic strengths. Hydrogels were evaluated for polymer volume fraction, solvent interaction parameter, molecular weight between crosslinks, number of links per polymer chain, diffusion coefficient, sol–gel fraction and porosity. To demonstrate the release pattern of the drug, zero-order, first-order, higuchi and korsmeyer-peppas models were applied. Quality and consistency of hydrogels was examined by FTIR and surface morphology of hydrogels was examined by SEM. Results Decrease in swelling and in drug release was seen by increasing content of ethylene glycol dimethacrylate. A remarkable high swelling was observed at high pH indicating the potential of this hydrogel for delivery of drugs to intestine. By increasing the concentration of ethylene glycol dimethacrylate, porosity decreased. Order of release was observed first order in all cases and the mechanism was non–fickian diffusion. FTIR confirmed the formation of network. SEM results showed the incorporation of drug. Conclusion The prepared hydrogels can be suitably used for targeted drug delivery to the intestine.

Purpose: To assess the impact of pharmacist-led multifactorial interventions on health parameters, medication adherence, and disease-related knowledge among type 2 diabetic patients in southern Punjab, Pakistan.Methods: The effect of intervention was evaluated by randomly assigning patients into control group (n = 170), receiving conventional medical care, and intervention group (n = 178), receiving predefined specialized care. The primary outcome of this intervention study was improvement in glycemic control which was assessed by measuring fasting blood glucose and glycosylated haemoglobin (HbA1c) values.Results: The outcomes obtained clearly show the role of pharmacist counseling in the control of type 2 diabetes while improving fasting blood glucose (FBG) and HbA1c levels, reduction in Body Mass Index (BMI), improvement in disease knowledge as well as reduction in smoking. The intervention significantly reduced BMI and waist circumference by a difference of 1.87 (p = 0.014) and 1.27 (p = 0.002) between control and intervention groups. Glycemic control was significant within the intervention group, as evident by a reduction in fasting blood glucose level {-19.26 mg/dL (p = 0.003)} and HbA1c level {-1.01 % (p < 0.001)} compared to control group. The mean difference in glycemic control between both groups was insignificant but mild reductions were seen in fasting blood glucose (-11.95 mg/dL, p = 0.11) and HbA1c (-0.43 %, p = 0.12). A significant increase in disease-related knowledge was seen in the intervention group, compared to the control group which was evident by mean differences in compliance (p = 0.003), foot-care (p < 0.001) and self-monitoring of blood glucose (p = 0.001).Conclusion: The purpose of study was achieved in that it demonstrates that pharmacists can play a pivotal role in improving glycemic control in diabetic patients and that involvement of pharmacists in diabetic clinics is beneficial to the patients in terms of medication adherence and promotion of healthy lifestyle.Keywords: Diabetes, Intervention, Medication adherence, Glycemic control, BMI, HbA1c

Flurbiprofen is a potent non-steroidal anti-inflammatory drug, prescribed commonly for musculoskeletal and joint disorders like arthritis. It is well established that drug degradation during storage and transportation is of particular issue in tropical countries like Pakistan, having areas with temperature variations from 0 o C (Muree, Islamabad, Sawat and Azad Jammu Kashmir) to 50 o C (Sibi, Jackababad, Nawabshah, Larkana, Multan and Bahawalpur) and some areas with high relative humidity (Karachi). Present study was designed to evaluate five different national brands of flurbiprofen 100 mg film coated tablets by accelerated stability studies and examined for the parameters of hardness, disintegration, dissolution and assay for drug concentration in formulation after one, three and six months duration at controlled tropical conditions of temperature and relative humidity. Dosage forms of all selected national brands were found stable even after expiry date.

We report synthesis, characterization, and drug release attributes of a series of novel pH-sensitive poly(acrylic-co-vinylsulfonic) acid hydrogels. These hydrogels were prepared by employing free radical polymerization using ethylene glycol dimethacrylate (EGDMA) and benzyl peroxide (BPO) as cross-linker and initiator, respectively. Effect of acrylic acid (AA), polyvinylsulfonic acid (PVSA), and EGDMA on prepared hydrogels was investigated. All formulations showed higher swelling at high pHs and vice versa. Formulations containing higher content of AA and EGDMA show reduced swelling, but one with higher content of PVSA showed increased swelling. Hydrogel network was characterized by determining structural parameters and loaded with isosorbide mononitrate. FTIR confirmed absence of drug polymer interaction while DSC and TGA demonstrated molecular dispersion of drug in a thermally stable polymeric network. All the hydrogel formulations exhibited a pH dependent release of isosorbide mononitrate which was found to be directly proportional to pH of the medium and PVSA content and inversely proportional to the AA contents. Drug release data were fitted to various kinetics models. Results indicated that release of isosorbide mononitrate from poly(AA-co-VSA) hydrogels was non-Fickian and that the mechanism was diffusion-controlled.

Artemisinin (ARMN) is a drug of choice against drug-resistant malaria especially due to Plasmodium falciparum. Being poorly soluble in water, its solid dispersions with nicotinamide (NA) were prepared at various drug-carrier ratios (1:1, 1:4, 1:6, 1:8, 1:10) by solvent evaporation and freeze drying methods. These solid dispersions were characterized by differential scanning calorimetery (DSC), fourier transform infrared spectroscopy (FTIR), X-ray diffraction patterns (XRD), phase solubility and dissolution studies. Artemisinin and nicotinamide both were found completely crystalline as shown by their XRD patterns. Physical mixtures (PMs) showed decreased intensity in their XRD patterns while solid dispersions by solvent evaporation method (SLVPs) exhibited displaced angles and decreased intensity whereas freeze dried solid dispersions (FDSDs) showed least number of peaks having low intensity and maximum displaced angles. DSC thermograms of drug-carrier ratios at 1:1-1:4 showed lower melting temperature than artemisinin and nicotinamide in all preparations. Endothermic temperature of artemisinin in PMs and SLVPs increased with rise of nicotinamide content upto 1:6 ratio followed by decline. All samples showed crystallization temperature below the artemisinin except drug-carrier ratio 1:6 of PMs while δH value was minimum at this ratio. FDSDs produced lowest endothermic temperature than corresponding PMs and SLVPs. SLVPs exhibited band shifting in both functional and fingerprint region compared to respective PMs as exhibited by their FTIR spectra. FDSDs and SLVPs showed different nature of bonding among artemisinin and nicotinamide. FDSDs produced strongest CONH(2) bonding followed by SLVPs and PMs respectively. PMs produced significantly higher aqueous solubility and rate of dissolution as compared to artemisinin alone. SLVPs exhibited improved solubility and dissolution profile corresponding to PMs. FDSDs showed highest release rate and aqueous solubility followed by SLVPs and PMs at all ratios. PMs and SLVPs showed their highest dissolution profile at 1:6 drug-carrier ratio followed by gradual decrease while FDSDs progressed in dissolution rate with increase of nicotinamide content successively upto maximum at 1:10 ratio.

In this study pH sensitive, biocompatible and controlled released hydrogels were prepared and their localized drug delivery effect was analyzed. Polycaprolactone and acrylic acid (PCL/AA) were reacted by free radical polymerization and developed inter penetrating polymeric network (IPN) hydrogels. Benzylperoxide was used as initiator and N, N methylenebisacrylamide [NNMBisAm] was employed as a cross-linking agent. Different concentrations of monomer, polymer and cross-linking agent were used and the reaction parameters were optimized. The obtained PCL/AA hydrogels were fully characterized by Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), and thermogravimetric analysis (TGA) that determined the polymer structure, its morphology and strength respectively. Verapamil, a calcium channel blocker was loaded by incubation of polymerization method. Controlled release Verapamil hydrogel was developed due to its low solubility; low permeability and having very short half life of 1.2-2 h. The dynamic swelling, equilibrium swelling and drug release were carried out in a buffer solution of pH 1.2, 4.5 and 6.8. Concentration of Acrylic acid showed direct, while Polycaprolactone inverse relation to swelling and drug release due to their hydrophilic and hydrophobic nature respectively. Cross-linking agent also had the contrary effect on swelling. Diffusion coefficient (D) of hydrogels was determined by using Flory-Rehner theory. Drug release and swelling data were analyzed by different kinetic models, like Zero order, First order, Higuchi, Korsmeyer's and Peppas. The release and diffusion was best described by the first order kinetics where n value was0.5 for all the formulations indicating Fickian drug release mechanism.

Solid dispersions of artemether (ARM), a poorly soluble drug, were prepared using polyvinylpyrrolidone (PVPK25, MW 25000) and polyethyleneglycol (PEG4000, MW 4000) as excipients. These dispersions were studied by physical mixture, freeze-drying, and melting methods. They were characterized by X-ray diffraction pattern, fourier transform infrared spectrophotometry, differential scanning calorimetery, and dissolution studies. X-ray diffraction pattern revealed the complete crystalline nature of artemether, whereas physical mixtures, melt mixtures (MM), and freeze-dried solid dispersions (FDSD) of ARM-PVP and ARM-PEG showed reduced peak intensities with increased PVP/PEG content. PEG showed lower decreases in intensity than PVP preparations. Differential scanning calorimetery also confirmed this finding by showing either a small or absent endotherm. Red shifts in O-H stretching vibrations of ARM were higher in the MM of ARM-PVP than its FDSD as exhibited by fourier transform infrared spectrophotometry. The carbonyl peak of PEG was blue shifted in MM and FDSD, whereas the C=O peak of PVP was red shifted in FDSD and MM, indicating different H-bonding by PEG and PVP with ARM. The rate of dissolution (phosphate buffer at pH 4.5) was improved up to 4-fold in MM and FDSD compared to artemether, and up to 50% compared to physical mixtures. The preparation of solid dispersions influenced the rate of dissolution at various drug-carrier ratios, i.e., the dissolution order of 1:1-1:4 ratio was MM > FDSD; FDSD > MM at 1:6-1:8 ratios of both ARM-PVP and ARM-PEG; and FDSD of ARM-PEG > FDSD of ARM-PVP > MM of ARM-PEG > MM of ARM-PVP at a 1:10 ratio.

Chitosan is a polysaccharide possessing biodegradable and biocompatible properties. Chitosan and its derivatives are used as excipients in drug delivery, as mucoadhesive polymers, and as a permeation enhancer for drug delivery in vitro at mucosal epithelia; and micelles of chitosan derivatives are used for solubilization of hydrophobic drug. Twenty-five samples of ammonium palmitoyl glycol chitosan were synthesized after reacting glycol chitosan with palmitic acid N-hydroxysuccinimide and methyl iodide with different concentration of hydrophobic and hydrophilic component. The objective was to identify suitable combinations of hydrophilicity and hydrophobicity which dissolve maximum water-insoluble camptothecin drug. In conclusion, the more hydrophilic and hydrophobic polymers are not suitable for solubilization of camptothecin.

Chronic kidney disease(CKD) is the cause of irreversible detoriation of renal function which leads to end stage renal disease(ESRD).incidence of end stage renal disease has increased dramatically during last 30 years and screening for early stages of chronic kidney disease is often suggested as preventive measure.the main cause of end stage renal disease are diabetes, high blood pressure,hyperlipidemia and obesity.obesity and increased BMI are the cause of kidney stone and chronic kidney disease.this reports aim to determine the prevalance of end stage renal disease in diabetic obese individuals and other problems that are more likely to be encountered in the end stage renal disease are cardiovascular risks in dialysis patients.GFR and creatinine clearance are used as the major diagnostic tool to determined the kidney function. calcium level is also used as predictive factor to determine the vascular calcification.

Hydrogels are being investigated recently for the bioactive molecules (in particular pharmaceutical proteins) controlled release, such as matrices, and for the living cells encapsulation. Biodegradable nature of hydrogels has created much interest for drug delivery systems. The original three-dimensional structure disintegrates into nontoxic substances to ascertain an excellent biocompatibility of the gel. Chemical cross-linking is the highly resourceful method for the formation of hydrogels having an excellent mechanical strength. Cross-linkers used in hydrogel preparation should be extracted from the hydrogels before use due to their reported toxicity. Physically cross-linked methods for preparation of hydrogel are the alternate solution of cross-linker toxicity.

The dissolution behavior of five commercially available brands of sustained release theophylline tablets was studied in phosphate buffer solutions of pH 1.2, 4.5, 5.5, 6.0 and 7.5 at 37 °C using the USP dissolution apparatus II (paddle method). Drug concentration in the samples was determined spectrophotometrically at 272 nm. For predicting the release characteristics of theophylline from selected commercially available tablets the data obtained in the dissolution studies was fitted into various mathematic models defining kinetic parameters of drug release like zero-order rate equation, first-order rate equation, Hixen-crowell cube root law, Higuchi equation and Korsemeyer-Peppas model. Tablets were subjected to weight variation test, hardness, drug content and in vitro release studies. The present study revealed that drug release increases with the increase of pH of the dissolution medium and also varies from brand to brand. Among the five selected brands, B1 and B4 showed better pH dependency and drug release behaviour. It has been suggested that possible reasons for difference in dissolution or drug release behaviour are the difference in the manufacturing techniques and the quantity of hydrophobic excepients used by different manufacturers, which retard the penetration of dissolution medium and ultimately decreases availability of drug in the solution., Colegio de Farmacéuticos de la Provincia de Buenos Aires