View at Google Scholar M. The reduced mathematical models for mean particle size, EE, average zeta potential, and PDI are presented by 4 to 7 rspoo, respectively. Further, such dense matrix, specifically when it is hydrophobic in nature, may be expected to favor less penetration of the dissolution medium in the tablets. Tenofovir is one of the first-line drugs used in the treatment of the human immunodeficiency virus HIV infected adults. No significant change in the appearance of characteristic peaks of pure drug spectra was observed fig.

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E-mail: moc. This article has been cited by other articles in PMC. Abstract The purpose of the present investigation was to prepare matrix tablets of naproxen using a hydrophobic polymer, i. The tablets were further coated with different concentrations of Eudragit S, a pH-sensitive polymer, by dip immerse method. In vitro drug release studies of tablets were carried out in different dissolution media, i.

The swelling studies of the optimized formulation were carried out. The physicochemical parameters of all the formulations were found to be in compliance with the pharmacopoeial standards. The effect of dissolution medium on the surface of matrix tablet was determined by using Scanning Electron Microscopy technique. The stability studies of all formulations were performed as per ICH guidelines.

With regard to release kinetics, the data were best fitted with the Higuchi model with non-Fickian drug release kinetics mechanism. The stability studies of tablets showed less degradation during accelerated and room temperature storage conditions for 6 months. The enteric-coated Eudragit S coated matrix tablets of naproxen showed promising site-specific drug delivery in the colon region.

Drug release at this site will ensure maximum therapeutic benefits. Various drug delivery approaches have been developed for colon-specific drug delivery, which include pH-sensitive system, time-dependent system, pro-drugs, and microflora-activated system to deliver anti-inflammatory agents to the sites of inflammation, and hence systemic drug absorption should be reduced as this leads to unwanted systemic side effects.

The high individual variability together with similarity in pH between the small intestine and the colon make the site specificity of pH-dependent system not very reliable. Although the relative consistency of transit times in the small intestine is because of the potentially large variation in gastric emptying time, the colon influx time cannot be exactly predicted.

The release of water-soluble drug from a water-soluble polymeric platform is often rapid, and therefore hydrophobic polymer may be included within the matrix formulation to offer a greater control drug release. Film coated matrix tablets using Eudragit NE30D produce a delivery system in which the release of diltiazem hydrochloride is pH independent from 1.

Eudragit RSPO was employed to delay the penetration of dissolution medium into the matrix, thereby decreasing drug release rate. So, the main purpose was to develop a single coating layer to prevent the drug release in stomach or small intestine and to slow down the drug release in the target site colon.

It has analgesic and antipyretic properties. However, its ability to inhibit prostaglandin synthesis may be involved in the anti-inflammatory effect. Inhibition of COX-1 is thought to be associated with gastrointestinal and renal toxicity, while inhibition of COX-2 provides anti-inflammatory activity.

All other chemicals and reagents used in study were of analytical grade. The wet mass was passed through a sieve No. The oversized granules retained on sieve No. Industries, Nakodar, India. Enteric coating of the matrix tablets The naproxen matrix tablets were further coated with Eudragit S solution. A different concentration 1, 1. The coating of the matrix tablets was performed by immersion in the coating solution followed by dip coating technique.

Characterization of granules Angle of repose The angle of repose of granules was determined by the funnel method. The accurately weighed granules were taken in a funnel.

The height of the funnel was adjusted in such a way that the tip of the funnel just touched the apex of the heap of the granules. The granules were allowed to flow through the funnel freely onto the surface. Bulk density Bulk density is defined as ratio of total mass of powder to the bulk volume of powder. Bulk volume is the volume occupied by a certain mass of powder when gently poured into a measuring cylinder. It was measured by pouring initially weighed powder into a measuring cylinder and the volume bulk volume was noted.

From this, the bulk density was calculated according to the formula mentioned below. Tapped density It is the ratio of total mass of the powder to the tapped volume of the powder. Volume was measured by tapping the powder for times and then the tapped volume was noted.

Compressibility index It indicates powder flow properties. Hausner ratio The Hausner ratio is a number that is correlated to the flowability of powder.

A Hausner ratio greater than 1. The smoothing of the spectra and the baseline correlation procedures were applied. The FTIR measurements were performed in the scanning range of cm—1 at ambient temperature. Physicochemical evaluation of naproxen matrix tablets Weight variation For estimating weight variation, 20 tablets of each formulation were weighed using an electronic balance Denver Instrument, Gottingen, Germany and the test was performed according to the official test.

Hardness The crushing strength of ten tablets was measured using Monsanto tablet hardness tester Interlabs, Ambala, India. Six tablets were weighed accurately from each batch of tablets and placed in the tumbling chamber and rotated at 25 rpm for a period of 4 min. Tablets were taken and again weighed. The percentage loss was determined by using the formula: Drug content Tablets were finely powdered and quantity of the powder equivalent to mg was accurately weighed and transferred to a volumetric flask containing 50 ml of phosphate buffer, pH 7.

The flask was shaken to solubilize the drug and the volume was made up to ml with phosphate buffer 7. The solution was filtered through a membrane filter 0.

The dissolution media with pH 1. The in vitro drug release experiments were performed at pH 1. Then pH 1. After performing the experiments for 3 h with pH 6. At regular time intervals, samples were withdrawn from the dissolution media and filtered with Whatman filter paper 0.

The graph was plotted against cumulative percentage drug release versus time. Male Wistar rats weighing g maintained on a normal diet were used for the study.

Using carbon dioxide CO2 , the rats were asphyxiated. The abdomens were cut, the ceci were isolated, ligated at both ends, and dissected. About 8 g of the cecal content was immediately weighed and transferred into ml of pH 7. Carbon dioxide CO2 was continuously passed through pooled content so as to keep the environment in anaerobic condition. After placing matrix tablet in pH 6. As cecum is naturally anaerobic, the experiment was carried out with continuous CO2 supply into the beakers.

To determine the release exponent for different batches of matrix tablet, the log value of percentage drug dissolved was plotted against log time for each batch.

Case II generally refers to the erosion of the polymeric chain, and anomalous transport non-Fickian refers to a combination of both diffusion and erosion controlled drug release. These tablets were glued to a piece of glass slide. The glass slide and tablets were weighed initially W1. The tablets were placed in different dissolution media pH 1. The swollen tablets were taken out at predetermined time intervals, and using tissue paper, excess of water on their surface was carefully removed and tablets were reweighed W2.

The study was carried out over a period of 12 h and the tablets were observed for rupturing. Prior to examination, samples were gold sputter-coated to render them electrically conductive.

The tablets were analyzed after 0 day, 1 month, 2 months, 3 months, and 6 months. At the end of the study period, the tablets were observed for the change in physical appearance, color, and drug content. The parameters for evaluation of granules are depicted in Table 2. Similarly, bulk density and tap density of all the formulation batches from F1 to F12 were found to be from 0. The Hausner ratio of all formulation batches from F1 to F12 was found to be from 1.

The Hausner ratio less than 1.


Eudragit Rspo PDF

Users requiring more precise data for scientific or engineering calculations can click on the property value to see the eudrayit value as well as raw conversions to equivalent units. Matrix systems are widely used in oral controlled drug delivery because of their flexibility, cost effectiveness, low influence of the physiological variables on its release behavior and broad regulatory acceptance [ 67 ]. Therefore, to maintain the oral delivery route, formulating the drug into polymeric nanoparticles is essential for improving the bioavailability. Where R and UR are the released and unreleased percentages, respectively, at time t ; k 1k 2k 3k 4and k 5 are the rate constants of zero-order, first-order, Higuchi matrix, Peppas-Korsmeyer, and Hixon-Crowell model, respectively. MatWeb is intended for personal, non-commercial use. Their results indicated that the drug had a solubility of The resultant benefit is a reduction of therapeutic dose, increased bioavailability, and limitation of toxic side-effects. The samples were prepared using a double adhesive tape stuck to an aluminium stub.



E-mail: moc. This article has been cited by other articles in PMC. Abstract The purpose of the present investigation was to prepare matrix tablets of naproxen using a hydrophobic polymer, i. The tablets were further coated with different concentrations of Eudragit S, a pH-sensitive polymer, by dip immerse method.


Eudragit RSPO

Tausida Sustained release formulation that would maintain plasma level for h might be sufficient for daily dosing of metformin. The composition of various formulations of the tablets with their codes is listed in Table 1. However, the mixtures were continued to be sonicated at different time frames and were left to stir overnight to aid size reduction and to evaporate solvent present. The quadratic model of zeta potential is shown in where, and represent ratio of a polymer to a drug, concentration of a surfactant, and sonication time, respectively, and and are interaction effects between ratio of a polymer to a drug and sonication time and concentration of a surfactant and sonication time while are quadratic effect.

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