Matrix-type Drug Delivery System Research Articles

Development and characterization of matrix-type drug delivery system for the treatment of Overactive Bladder

Development and characterization of matrix-type drug delivery system for the treatment of Overactive Bladder

FORMULATION AND EVALUATION OF METFORMIN HYDROCHLORIDE SUSTAINED RELEASE MATRIX TABLETS

Objective: Now a days as very few antidiabetic drugs are coming out of research and development and some existing drugs are showing several side effects when administered orally, multiple times in a day, hence change in the operation is a suitable and optimized way to make some drug more effective by slight alteration in the drug delivery. Matrix type drug delivery systems of an antidiabetic drug like Metformin Hydrochloride, is an interesting and promising option when developing an oral sustained release system
 Methods: An appropriately designed controlled release drug delivery system can be a major advance towards solving problems concerning the targeting of a drug to a specific organ or tissue and controlling the rate of drug delivery to the target sites. This research work is made in designing of sustained release dosage form of Metformin Hydrochloride by wet granulation method employing both Xanthan Gum and Hydroxy Propyl Methyl Cellulose (HPMC K4M) as a rate controlling polymer.
 Results: The development of oral sustained release systems has been a challenge to formulation scientists due to their inability to restrain and localize the system at targeted areas of the gastrointestinal tract. From all the formulation trial batches, formulation F7 shows the best results. It has been observed that HPMC K4M alone cannot give satisfactory drug release profile but the blend of HPMC K4M and Xanthan gum together give the best drug release kinetics.
 Conclusion: The drug release mechanism from the matrix tablets follows Fickian diffusion with first order kinetics. Thus, sustained release matrix tablets of metformin hydrochloride can be expected to reduce the frequency of administration and decrease the dose dependent side effects

Sustained Release Drug Delivery System with the Role of Natural Polymers: A review

An appropriately designed sustained release dosage form is opted to be a major goal in solving the problems which arises regarding the targeting of a drug to a specific organ or tissue and for controlling its rate of delivery to the target site. The development of oral sustained release system has proven to be a major challenge to formulation scientist due to their inability to restrain as well as localize the system at targeted areas of the gastrointestinal tract. Therefore the development of matrix type drug delivery system is promising option regarding the development of an oral sustained release system. There is availability of wide variety of polymers which helps the formulation scientist to develop sustained/controlled release products. The attractiveness of these dosage forms is increasing because of their awareness towards toxicity and ineffectiveness when administered by oral route in the form of tablets and capsules. Numerous advantages are provided by sustained release products over conventional dosage forms through optimizing various bio-pharmaceutics, pharmacokinetic and pharmacodynamics properties of drugs and finally leads to reduction in dosing frequency to such an extent that only once daily dose is required for therapeutic management with maximum utility of drug with reduction in both local as well as systemic side effects. They can cure or control diseased condition in shortest possible time with smallest quantity of drug to assure greater patient compliance. Polymer swelling, drug dissolution and its diffusion are the known mechanisms for drug release through polymer network. Keywords: Oral drug delivery system, sustained release dosage form, matrix system, polymer swelling, drug diffusion.

A brief review on recent advances of extended release technology employed to design the oral dosage forms

The benefits offered by modified release systems include reduced dosing frequency with improved patient compliance, better and more uniform clinical effects with lower incidence of side effects and possible enhanced bioavailability. Characteristics of a modified release system as stated by USP is “The drug release characteristics of time, course and / or location are chosen to accomplish therapeutic or convenience objectives not offered by conventional dosage forms” [1]. This includes technologies that modify the site of drug delivery. Extended release dosage forms extend the life of a drug so that dosage regiment shifts from 3 times a day dosing just once or twice a day. The successful formulation of a modified release device requires a comprehensive understanding of the mechanism of drug release from the macroscopic effects of size, shape and structure through to chemistry and molecular interaction. Multiparticulate dosage forms shown to be less prone to food effects than monolithic and is often the preferred formulation for extended and / or delayed release. Extended release drug formulation is conventionally produced as compressed tablets by hydrogel tablet technology. To produce these extended release tablet dosage forms, active ingredient is conventionally compounded with cellulose ethers like methylcellulose, ethyl cellulose or hydroxyl propyl methylcellulose with or without excipients and the resulting mixture is pressed into tablets. When the tablets are orally administered, cellulose ethers in the tablet swell upon hydration from moisture in the digestive system, thereby limiting exposure of active ingredient to moisture. As the cellulose ethers are gradually leached away by moisture, water more deeply penetrates the gel matrix and the active ingredient slowly dissolves and diffuses through the gel, making it available for absorption by the body. An appropriately designed controlled release drug delivery system can be a major advance towards solving problems concerning the targeting of a drug to specific organ or tissue and controlling the rate of drug delivery to the target sites. The development of the oral controlled release system has been a challenge to formulation scientists due to their inability to restrain and localize the system at targeted areas of the gastro intestinal tract. Matrix type drug delivery systems as carriers for the active ingredients are interesting and promising option in developing an oral controlled release system. Tablets are the preferred dosage form for many drugs and are still the most widely used formulations for both new and existing modified released products.

A Brief Review on Sustained Release Matrix Type Drug Delivery System

Purpose : A review on sustained release drug delivery using polymer matrix with emphasis on its contemporary usage and future trends. Approach : An introduction to sustained release drug delivery system (SR DDS), followed by its rationale, advantages, disadvantages, criteria of a drug to be met to formulate sustained release formulations, classification of matrix tablets, classification of polymers, its mechanism and recent advancements. Finding : Recent studies indicate that sustained delivery for a very long period, in terms of months is possible using suitable polymer matrices. Also, challenging drug candidates such as proteins are now successfully delivered as sustained release dosage forms. Conclusion : Sustained release DDS, since 1940s has evolved in different types of dosage forms for sustained effect but future scope will be to treat chronic diseases providing sustained effect.

Construction of Matrix-type Drug Delivery System using Solid Phase Polymerization initiated by Plasma-induced Radicals

Construction of Matrix-type Drug Delivery System using Solid Phase Polymerization initiated by Plasma-induced Radicals

Moulded cross-linked chitosan matrix systems for controlled drug release

Matrix-type drug delivery systems were prepared by moulding and drying cross-linked chitosan gels in 24-well plates and they were evaluated in terms of their physical properties, drug content, surface morphology and swelling. Furthermore, the in vitro drug release profiles were subjected to kinetic modelling at two different pH values. In general, the moulded matrix systems showed statistically significantly slower drug release compared to immediate release tablets as measured by the mean dissolution time. Drug release from the moulded matrix systems prepared from chitosan cross-linked with tripolyphosphate was pH-dependent as can be seen from the release exponent value (n) of 0.75 at pH 5.8 (anomalous transport, erosion), while the n value was only 0.40 at pH 7.4 (Fickian diffusion). The matrix systems obtained from chitosan cross-linked with sodium lauryl sulphate showed higher swelling but mostly Fickian diffusional release (n = 0.25 at pH 7.4, n = 0.41 at pH 5.8).

Controlled Release Oral Dosage Forms: Some Recent Advances in Matrix Type Drug Delivery Systems

Controlled Release Oral Dosage Forms: Some Recent Advances in Matrix Type Drug Delivery Systems

Plasma techniques for preparation of controlled drug release system

Plasma-induced surface radicals formed on a variety of organic polymers have been studied by electron spin resonance (ESR), making it possible to provide a sound basis for future experimental design of polymer surface processing, i.e., plasma treatment. On the basis of the findings from such studies, several pharmaceutical applications in the field of drug engineering have been devised, which include preparation of double-compressed tablets for reservoir-type drug delivery system (DDS) of sustained- and delayed-release, and fabrication of functionalized composite powders applicable for matrix-type DDS by a mechanical application of plasma-irradiated polymer powder.

Development of silicone-based barrier devices for controlled delivery of spermicidal agents

Intravaginal devices (diaphragm and disc) were fabricated from silicone elastomer and evaluated for controlled release of Nonoxynol-9 (N-9). These intravaginal devices have good physical properties and reproducibility. A significant amount of N-9 was released within 2 min from vaginal devices; the release profile was found to follow Q vs. t 1/2 relationship. The release flux increased with increasing loading dose of N-9 from 10 to 40%, which followed a linear Q/t 1/2 vs. (2 A) 1/2 relationship, a typical characteristic of matrix-type drug delivery systems. The optimal loading dose of N-9 in diaphragms to achieve an appropriate release rate was of the order of 35%. The release flux of N-9 increased as the device shape changed from diaphragm to disc. Release flux of N-9 also increased with decreasing thickness of devices from 75 to 10 mil-inch. The release rate of N-9 from devices decreased as the duration of storage, after blending of N-9 into polymer parts before molding, increased. Spermicide-releasing disposable vaginal diaphragms containing N-9 were physically and chemically stable under various storage conditions for 16 weeks. Spermicide-releasing disposable vaginal diaphragms can offer a promising approach for achieving a controlled release rate of N-9 and consequent fertility control.

Drug permeation through skin from matrix-type drug delivery systems

Nitroglycerin permeation through hairless mouse skin from various matrix-type transdermal delivery systems has been explained fairly well on the basis of a two-layer skin model. The diffusivity and solubility of the drug in the stratum corneum and in the viable skin have been calculated. The diffusivity in the stratum corneum was found to be affected by the type of delivery system, while that in the viable skin was hardly influenced by the delivery system. The loading dose, diffusivity and solubility of the drug in the delivery system were found to be the important design parameters for skin-control transdermal drug delivery and, therefore, the transdermal delivery system has to be optimized by controlling these three parameters to achieve a maximum rate of skin permeation with minimum drug loading dose.

Intrinsic Release Rate from Matrix-type Drug Delivery Systems

A simple method was presented for evaluation of the intrinsic release rate from a matrix-type drug delivery system. The effect of the hydrodynamic diffusion boundary layer on the rate of drug release was corrected to obtain the release profile without any diffusion boundary layer effect. The experimental release data was logically explained in terms of the intrinsic rate of release evaluated from the present method.

Mechanism of Transdermal Controlled Nitroglycerin Administration (III) Control of Skin Permeation Rate and Optimization

AbstractA mathematical model was developed to correlate the drug permeation rate through the skin with the drug release rate from a matrix-type drug delivery system. Experiments were carried out using hairless mouse abdominal skin mounted on a recently-developed and hydrodynamically well-calibrated Keshary-Chien skin permeation system. A matrix-type drug delivery system was designed to contain different loading doses of nitroglycerin and to study the effect of drug loading variation on the rate of drug release, the rate of skin permeation and the equilibrium concentration of nitroglycerin in the skin.Results indicated that the stratum corneum plays a significant rate-limiting role in the skin permeation of nitroglycerin across the intact skin, yielding a constant skin permeation profile. The permeation rate across the intact skin was observed to increase with the increase in the drug release flux initially and then levelled off in a hyperbolic fashion. Various constants were obtained from the reciprocal p...

Mechanistical Analysis of Release Kinetics for Lipophilic Drug from Matrix-Type Drug Delivery Devices

The release kinetics of lipophilic drug from hydrophobic polymer-based matrix-type drug delivery system was studied. Using the “intrinsic formula”, several experimental problems can be analyzed and solved. The results reveal that intrinsic release, calculated from the model, shows the true properties of the drug delivery system, which might have been disguised by the boundary layer effect. The results also demonstrated the needs of maintaining sink condition and uniform distribution of dispersed phase in studying the matrix diffusion-controlled drug release.