MUCOADHESIVE DRUG DELIVERY SYSTEM THESIS

An ideal polymer should exhibit the ability to incorporate both hydrophilic and lipophilic drugs, show mucoadhesive properties in its solid and liquid forms, inhibit local enzymes or promote absorption, be specific for a particular cellular area or site, stimulate endocytosis and finally to have a broad safety range Lee, Park, Robinson, Mucin is the most important glycoprotein of mucus and is responsible for its structure. Nonionic polymers, including hydroxypropylmethylcellulose, hydroxyethylcellulose and methylcellulose, present weaker mucoadhesion force compared to anionic polymers Mortazavi, Moghimi, Such dressings are poor at staying in place at the vulva, where shear forces are high in mobile patients. Blue polymer layer and red mucus layer before contact; b Upon contact; c The interface becomes diffuse after contact for a period of time. Other features associated with the development of controlled drug delivery systems using bioadhesive molecules include a decrease in drug administration frequency and an increase in patient compliance to the therapy Woodley,

Mucoadhesion should not be confused with bioadhesion; in bioadhesion, the polymer is attached to the biological membrane and if the substrate is mucus membrane the term mucoadhesion is used. It should adhere quickly to moist tissue and possess some site specificity. Environment-related factors include pH, initial contact time, swelling and physiological variations. Bioadhesive capacity and immunoadjuvant properties of thiamine-coated nanoparticles. J Photochem Photobiol B.

This review article aims to provide an overview of the various aspects of mucoadhesion, mucoadhesive materials, factors affecting mucoadhesion, evaluating methods, and finally various mucoadhesive drug delivery systems buccal, nasal, ocular, gastro, vaginal, and rectal. In-vitro bioadhesion of carbopol hydrogels.

Increase in compression force resulted in a decreased in vitro and in vivo drug release while giving the best in vivo mucoadhesive and hydration time.

According to the movement, the control system increases the magnetic current and the resulting magnetic force F m pulls the sphere to its initial position, separating it from thesks tissue.

mucoadhesive drug delivery system thesis

Bioadhesive systems applied to mucous membrane are frequently defined as mucoadhesive, but the terms are interchangeable Leung, Robinson, In this later case, porcine stomach, intestinal and buccal mucus were tested, and also jejunum from rabbits. An in-vitro method for buccal adhesion studies: In this test, the force required to remove the formulation from a model membrane is measured, which can be a tnesis composed of mucin Bruschi et al.

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Mucoadhesive drug delivery systems

Other physiological variations can also occur with diseases Lee, Park, Robinson, If the local pH is above the p K of the polymer, it will be largely ionized; if the pH is below the p K of the polymer, it will be largely unionized. Cross-linking and Swelling Cross-link density is inversely proportional to the degree of swelling. Application of dosage forms to mucosal surfaces may be of benefit to drug molecules not amenable to the oral route, such as those that undergo acid degradation or extensive first-pass metabolism.

Both keratinized and nonkeratinized epithelial cells present depending upon location within nasal cavity. A prolonged effect upon the dermal administration of creams, solutions, and lotions is unexpected, since such preparations can be easily removed from the skin by moisture, temperature, and physical movements Shin et al. According to the adsorption theory, after an initial contact between two surfaces, the materials adhere because of surface forces acting between the chemical structures at the two surfaces.

mucoadhesive drug delivery system thesis

Photodynamic therapy of vulval neoplasias and mucoadhesiv Although measures taken by this method are reproducible, the technique involves no biological tissue and therefore does not provide xrug realistic simulation of biological conditions Wong, Yuen, Peh, In the last two decades, mucoadhesion has shown renewed interest for prolonging the residence time of mucoadhesive dosage forms through various mucosal routes in drug delivery applications.

Moreover, it was observed that tablets prepared with the lowest force gave the best results, in comparison with tablets prepared with highest forces causing pain during in vivo application, needing to be detached by human volunteers.

mucoadhesive drug delivery system thesis

Ex vivo evaluation of bioadhesive films for buccal delivery of fentanyl. This structure has the appearance of highly viscous transparent gel. Bioadhesive properties and rheology of polyether-modified poly acrylic acid hydrogels. Recently, mucosal vaccines have been introduced in immunization to induce a systemic immune response.

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A segment of intestinal tissue is removed from the rat, everted, and mucoadhexive of its ends sutured and filled with saline.

Mucoadhesive drug delivery systems

This test is based on the passage of a mucin suspension through a sensor containing the immobilized polymer. Tetheres structures and site-specific surfaces. If the particle approaches the mucous xrug, it will come into contact with repulsive forces osmotic pressure, electrostatic repulsion, etc. Gene transfer is considered to be a promising alternative for the treatment of several chronic diseases that affect the ocular surface.

An ideal polymer should exhibit the ability to incorporate both hydrophilic and lipophilic drugs, show mucoadhesive properties in its solid and liquid forms, inhibit local enzymes or promote absorption, be specific for a particular cellular area or site, stimulate endocytosis and finally to have a broad safety range Lee, Park, Robinson, Another test using the same principle, the Biacore test, was applied for the analysis of mucoadhesion by Takeuchi et al.

In tensile and shear experiments, the stress is uniformly distributed over the adhesive joint, whereas in the peel strength stress is focused at the edge of the joint.

Various clinical trials of contraceptive gels are also ongoing, with a view to determine their effectiveness.

Mucoadhesive drug delivery systems

Reinhart and Peppas[ 12 ] reported that the diffusion coefficient depended on the molecular weight of the polymer strand and that it decreased with increasing cross-linking density. Due to their high specificity, antibodies can be a rational choice as polymeric ligand in the development of site-specific mucoadhesives.

In vitro and ex vivo tests. It was found that when the GRFs were dried and immersed in gastric juice, they swelled rapidly and released their drug payload in a zero-order fashion for a period of 24 h.

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