Chitosan-clay nanocomposite as a drug delivery system of ibuprofen

Chitosan/montmorillonite nanocomposite films were prepared by the solvent evaporation method to immobilize the drug ibuprofen (IBU) and delay its release in a medium that simulates the environment of the gastrointestinal tract. The effects of montmorillonite, at different mass proportions (10, 20, and 50%), on the morphological and physical properties of the films were studied. The samples were characterized by X-ray diffraction (XRD), Infrared Spectroscopy (FTIR), Scanning Electron Microscopy (SEM), degree of swelling, drug encapsulation, and drug release efficiency. According to the XRD it was evidenced that the incorporation of montmorillonite to chitosan led to the formation of nanocomposites of ordered morphology. The infrared spectra confirmed the good interaction between montmorillonite and chitosan by the formation of nanocomposites. This fact, which favored the imprisonment of the IBU, reduced the diffusion coefficient in the studied systems. The micrographs comproved the formation of dense and uniform films. The controlled release profile, especially for the nanocomposite with 10% clay mass, showed a slow drug release rate. The incorporation of montmorillonite at different proportions produced different morphologies, with good encapsulation efficiency and an adequate profile for the controlled release of the drug.

Design, Fabrication and Characterization of Nanoliposomes Containing Snake Venom of Pseudocereaster percius

Background: Development of antivenom or antidote requires the repetition of immunization of large animals, such as horses and goats, which ultimately releases the IgG immunoglobulin produced in the serum specimen. As snake venom involves a variety of proteins and enzymes getting administered into the animal, this process can inflict significant harm to the animal, therefore choosing carriers that can deliver the least amount of venom could be a safer option for animal immunization Objective: In this research, nanoliposomes were used to encapsulate venom as a protected cargo for immunization. We used two distinct liposomal formulations to entrap the venom: 1,2-distearoyl-sn-glycero-3-phosphocholine, 1,2-distearoyl-sn-glycero-3-phospho-(1′-rac-glycerol) associated with cholesterol in one formulation and dimethyldioctadecylamonium (Bromide salt) paired with cholesterol in the other. Method: Liposomal formulations prepared by solvent evaporation method and the venom was encapsulated in liposomes and evaluated for size and zeta potential. Meanwhile, encapsulation efficiency, venom release percentage, and phospholipase activity have all been analyzed. Results: The findings revealed that dimethyldioctadecylamonium (Bromide salt) combined with cholesterol had the highest encapsulation efficiency. In this formulation, the venom release rate had a steady-state profile. The lack of phospholipase activity in this formulation may be due to a bromide group in the liposomal structure that could be useful for immunization. Conclusion: Liposomal formulations, which do not have the active site of the snake venom enzymes, could be used for venom encapsulation.

A simple and high efficient composite based on g-C3N4 for super rapid removal multiple organic dyes in water under sunlight

A simple and high efficient porous composites via the solvent evaporation method using g-C3N4 and NiSO4 was developed. It can super rapidly remove multiple organic dyes in water including rhodamine...

FORMULATION AND INVITRO EVALUATION OF SOLID DISPERSION TABLETS OF SILYMARIN

Objective: The research aims to formulate and evaluate Solid Dispersion tablets of Silymarin. Methods: Solid dispersions of Silymarin were prepared with various concentrations of carriers by using solvent evaporation method. The prepared solid dispersions were compressed into tablets by using 8 mm punch rotary tablet punching machine, with the hardness of 3.5kg /cm2.The formulated tablets were evaluated for various quality control parameters. Results: Silymarin was mixed with various proportions of excipients which showed no drug-excipients interactions. The precompression blend of Silymarin solid dispersions were characterized with respect to angle of repose, bulk density, tapped density, Carrs index and Hausners ratio. The precompression blend of all the batches indicated good to fair flowability and compressibility. Conclusion: The tablet passed all the tests. Among all the formulations F4 formulation containing, Drug and PEG 4000 in the ratio of 1:4 showed good result that is 94.95 % in 60 minutes. As the concentration of polymer increased the drug release was increased. While the formulations containing PEG 6000 showed less release. Hence from the dissolution data it was evident that F4 formulation is the better formulation.

Evaluation of the Influence of Stirring Speed on the Release Kinetics of Fexofenadine HCl Polymeric Microspheres

Microspheres, a potential drug delivery approach, has opened a new era for attaining versatile release patterns needed. By optimizing the formulation variables, they can be prepared to obtain targeted release, immediate release, sustained release patterns. The release of the active drug material depends upon a number of formulation parameters such as polymers, stirring speed (rpm), methodology, surfactants, etc. Fexofenadine hydrochloride (HCl) is a second generation antihistamine. Our present research has explored the effects of using different rpm (600- 1000 rpm) in preparing fexofenadine hydrochloride (HCl) microspheres by emulsion solvent evaporation method. The formulation is aimed to provide sustained release for the required long period with a high margin of safety. We used a blended mixture of Hydroxy Propyl Methyl Cellulose (HPMC) K 100 MCR and Eudragit RL100 polymers to have sustained-release microspheres. The impact of different rpm on Yield, drug encapsulation efficiency, flow properties, and dissolution pattern were appraised. We observed the release of the drug for 10 hours in phosphate buffer (pH 6.8) and evaluated the drug release spectrophotometrically. Our study finds that the release of fexofenadine HCl from the microspheres was significantly increased with drug loading. We found the dosage forms to follow Higuchi release kinetics and Hixson-Crowell release kinetics the most, indicating successful achievement of sustained-release pattern in the dosage form. The change in drug release rate was statistically significant for variation in the stirring rate. We found that 600 rpm was the most optimized stirring rate for preparing microspheres in the emulsion solvent evaporation method.

Formulation Development and Evaluation of Sustained Release Microsphere of Levetiracetam

The aim of the present work was to develop and evaluate of oral microsphere of Levetiracetam to reduce the frequency of dosing by achieving 12 hours sustained drug release. The microsphere formed will also mask the bitter taste of the drug and thus increase the compatibility of the drug with the patients. Levetiracetam is a second-generation anti-epileptic agent useful in the treatment of partial onset and monoclinic seizures. It has a short half life of 7 hours and its recommended dose is 500 mg twice a daily. Microspheres are suitable drug delivery system for such drug candidate. For these reasons it is must to formulate a suitable dosage form by which it will be easier to administer the dose and also to get a sustained drug release hence microsphere was prepared using solvent evaporation method. Preformulation studies were carried out to rule out any drug polymer interaction by FTIR technique. In this study formulation was done solvent evaporation method using different percentage of HPMC– K 100, HPMC- K 15 and coated with Eudragit S100. Drug, polymer and physical mixture were evaluated for in compatibility study by Fourier transforms infrared spectroscopy. All the batches of microsphere (F1 to F5) were subjected for in vitro dissolution. Microsphere was evaluated for surface morphology, micromeritics properties, entrapment efficiency and in vitro drug release. The entrapment efficiency of microsphere ranged from 71.16%-73.66%. The size of the prepared microsphere ranges between 42.8 µm to 55.64 µm which was found to increase with increase in RPM at same polymer ratio. Micromeritics studies showed good flow properties. Among the microsphere batches, F5 was observed as an optimized batch as its formulation with polymer i.e. Eudragit-S 100 and HPMC-K 100 was found to be release in sustained manner. The F-5 batch shows is 79.45% drug release at the end of 7 hrs and its stability study indicate that these microspheres were stable at selected temperature and humidity

Sustainable Stabilizer-Free Nanoparticle Formulations of Valsartan Using Eudragit® RLPO

The bioavailability of the antihypertensive drug valsartan can be enhanced by various microencapsulation methods. In the present investigation, valsartan-loaded polymeric nanoparticles were manufactured from Eudragit® RLPO using an emulsion–solvent evaporation method. Polyvinyl alcohol (PVA) was found to be a suitable stabilizer for the nanoparticles, resulting in a monodisperse colloid system ranging in size between 148 nm and 162 nm. Additionally, a high encapsulation efficiency (96.4%) was observed. However, due to the quaternary ammonium groups of Eudragit® RLPO, the stabilization of the dispersion could be achieved in the absence of PVA as well. The nanoparticles were reduced in size (by 22%) and exhibited similar encapsulation efficiencies (96.4%). This more cost-effective and sustainable production method reduces the use of excipients and their expected emission into the environment. The drug release from valsartan-loaded nanoparticles was evaluated in a two-stage biorelevant dissolution set-up, leading to the rapid dissolution of valsartan in a simulated intestinal medium. In silico simulations using a model validated previously indicate a potential dose reduction of 60–70% compared to existing drug products. This further reduces the expected emission of the ecotoxic compound into the environment.

Preparation and Characterization of a Hybrid Complex of Cyclodextrin-Based Metal–Organic Frameworks-1 and Ascorbic Acid Derivatives

Cyclodextrin-based metal–organic frameworks-1 (CD-MOF-1) prepared using potassium hydroxide, ethanol, and γ-cyclodextrin (γ-CD) has been reported as a new type of MOF for the development of pharmaceutical formulations. The present study aimed to investigate the physicochemical properties of ascorbic acid derivatives (L-ascorbyl 6-palmitate (ASCP); L-ascorbyl 2,6-palmitate (ASCDP)) complexed with CD-MOF-1 by a solvent evaporation method. Powder X-ray diffraction revealed that the crystal diffraction pattern of CD-MOF-1 changed from α-type to β-type when prepared by a solvent evaporation method. For ASCP/CD-MOF-1 = 1/2 and ASCDP/CD-MOF-1 = 1/4 evaporated samples, the crystal diffraction peaks derived from ASCP and ASCDP disappeared, indicating a β-like behavior. Differential scanning calorimetry results revealed that the endothermic peaks of evaporated samples (ASCP/CD-MOF-1 = 1/2 and ASCDP/CD-MOF-1 = 1/4) were not detected due to melting. Furthermore, intermolecular interactions were observed in the hydrogen bonds between the CH groups of the side chains of ASCP and ASCDP and the OH group of CD-MOF-1 in (ASCP/CD-MOF-1 = 1/2) and EVP (ASCDP/CD-MOF-1 = 1/4), based on the near-infrared absorption spectroscopy analysis. CD-MOF-1 did not form inclusion complexes with the lactone rings of ASCP and ASCDP, but with the lipophilic side chains. These results suggested that CD-MOF-1 may be useful in preparing novel drug carriers for ASCP and ASCDP.