Drug Dev Ind Pharm. Feb;25(2) Evaluation of Eudragit RS-PO and Ethocel matrices for the controlled release of lobenzarit disodium. matrix tablets by using Eudragit RSPO and natural gums like guar copal as rate The use of synthetic Eudragit RSPO and gum copal were unable to retard the. Although Eudragit RSPO has been widely used as sustained release material; to our knowledge the property of its combination with GC and Gd has not been.

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An identical release profiles were observed in both dissolution media, which is due to the fact that Eudragit RS PO is pH independent; the release of drug is dependent on the diffusion of the drug from the matrix of the polymer. Kinetic modeling of in vitro dissolution profiles revealed the drug release mechanism ranges from diffusion controlled or Fickian transport to anomalous type or non-Fickian transport.

Figure 2 provides the 3D response surface plots showing the change of particles size corresponding to the change of independent variables. Mathematical models were developed to understand the nature of the true uedragit between the input variables and the output variables of the system [ 32 ]. The influence of the polymer concentration in the tablets was also investigated.

Evonik EUDRAGIT® RS PO Copolymer

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. A graphical representation of an optimized mean particle size is given in Figure 6: Additionally, there was compatibility between drug and the polymer, meaning that, during the process of formulation, polymer has not reacted with the drug to give rise to eudraagit products; it is only physical mixture.


We appreciate your input. The authors declare that there is no conflict of interests regarding the publication of this paper.

Time-controlled release

This may be due to the reason that the gums in higher concentrations in the tablets might have produced dense matrix around the drug particles, providing more barriers for them to escape and dissolve.

The tablets were prepared by wet granulation method. Similarly in Figure 3 ba higher EE was obtained with a decrease in ratio of a polymer to a drug and a maximum sonication time at a constant concentration of a surfactant. View at Google Scholar L. Property Data This page displays only the text of a material data sheet.

Cellulose ethers such as hydroxypropylmethylcellulose, sodium carboxymethylcellulose, Eudragit polymethacrylate polymer [ 89 ], ethyl cellulose [ 10 ] and some natural gums like guar gum and xanthan gum are widely used hydrophilic polymers as release retardants [ 11 ].

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.

This can be due to the fact that an increase in polymer concentration led to an enhancement of the concentration gradient between emulsion droplets and the continuous phase, as a result increasing the amount of drug partitioning into the continuous phase [ 38 ].

Matrix tablets, each containing mg metformin HCl were prepared by a conventional non-aqueous wet granulation technique.

Time-controlled Drug release

The most important characteristics of drug-bearing nanoparticles are size, encapsulation efficiency EEzeta potential, and drug release [ 14 ]. It can be seen from the plot that an increase in ratio of a polymer and concentration of a surfactant resulted in an increased mean particle size. View at Google Scholar U.


This could be attributed to an ionic electrostatic interaction between the drug and the polymer during formation of nanoparticles. Although Eudragit RSPO has been widely used as sustained release material; to our knowledge the property of its combination with GC and Gd uedragit not been evaluated.

It is also known as solvent displacement or interfacial deposition method and was developed about 40 years ago [ 18 ]. Tenofovir nanoparticles were prepared using modified nanoprecipitation method [ 24 ] in accordance with BBD Table 2. Subscribe to our Newsletter All our latest content delivered to your inbox. Factors with values that are less than 0. The contents, results, and technical data from this site may not be reproduced either electronically, photographically or substantively without permission from MatWeb, LLC.

The percentage errors between measured and predicted values were found to be insignificant.

The negative sign for the coefficients in the equation indicates a negative effect on responses, while the positive sign indicates a positive effect [ 8 ]. They are copolymers of acrylic and methacrylic esters compatible with oral drug administration [ 9 ]. The dissolution media used were ml of 0. The ammonium groups are present as salts and make the polymers permeable.

Small mean particle size was observed in Figure 2 b when sonication time was increased. The composition of various formulations of the tablets with their codes is listed in Table 1. Subsequently, nanoparticles eurdagit formed which turned the aqueous phase slightly milky with bluish opalescence.