Fluorescein, HPMC[ 68 ]. Ocular Mucoadhesive Drug Delivery Systems Drug administration to the eye is a challenge because there are several mechanisms tear production, tear flow, and blinking that protect the eye from the harmful agents. The experimental conditions of both tests differ and there are cases in which the techniques are complementary. Design and evaluation of a water-soluble bioadhesive patch formulation for cutaneous delivery of 5-aminolevulinic acid to superficial neoplastic lesions. Drug Dev Ind Pharm. Rate controlled rectal drug delivery in man with a hydrogel preparation.
This is used to investigate the influence of stress on the dynamic modulus, which should be obtained in the linear viscoelastic region, that is, the region where the material response is characteristic for its microstructure. Recent advances in polymeric technology have increased the potential of vaginal gels. Eur J Pharm Biopharm. Development and in vivo evaluation in humans. If the particle approaches the mucous surface, it will come into contact with repulsive forces osmotic pressure, electrostatic repulsion, etc. Peristaltic motions can contribute to this contact, but there is little evidence in the literature showing appropriate adhesion. Various clinical trials of contraceptive gels are also ongoing, with a view to determine their effectiveness.
The basics and underlying mechanisms of mucoadhesion.
Attraction and repulsion forces arise and, for a mucoadhesive to be successful, the attraction forces must dominate. The GIT of the rat was then cut into 20 equal segments and the radioactivity was measured. Preparation of thiomer microparticles and in vitro evaluation of parameters influencing their mucoadhesive properties.
Mucoadhesive drug delivery systems
Table 1 shows the chemical structures of several bioadhesive polymers commonly used in modern drug delivery. Using this technique, it is possible to perform a previous evaluation of the material’s adhesive capacity, evidencing mucoadhesion properties Bruschi, They can be incorporated into solid formulations, such as tablets, transdermal adhesives and microparticles, and into semisolid formulations including gels, ointments, pastes and suppositories Smart, This method is more frequently used to analyze solid systems like microspheres Chowdary, Rao,although there are also studies on semi-solid materials Bromberg et al.
Cevher[ ] aimed to prepare clomiphene citrate CLM gel formulations for the local treatment of human papilloma virus infections. The function of the rectum is mostly concerned with removing water. Mucoadhesive materials can improve bioavailability, drug absorption and transport while reducing undesirable systemic effects.
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, According to the literature, the depth of interpenetration required to produce an efficient bioadhesive bond lies in the range 0. Ramosetron, carbopol[ 73 ]. Mathiowitz, Chickering, Lehr, ; Hagerstrom, Gene transfer is considered to be a promising alternative for the treatment of several chronic diseases that affect the ocular surface.
Mucoadhesive drug delivery systems
Fracture energy g c can be obtained from the reversible adhesion work, W r energy required frug produce new fractured surfacesand the irreversible adhesion work, W i work of plastic deformation provoked by the removal of a proof tip until the disruption of the adhesive bondand both values are expressed as units of fracture surface A f.
It is feasible to design a bio muco adhesive system in different dosage forms, since the properties of adhesion largely depend on the features of the material used in its preparation Evangelista, This work, which causes the jucoadhesive of the macromolecules, is the yhesis of the change in viscosity. Considering pharmacokinetic parameters of human subjects under fasting conditions, bioavailability of riboflavin from a large size GRF was more than triple of that measured after administration of an immediate release formulation.
The wetting theory is perhaps the oldest established theory of adhesion.
But during the shear stress, the direction of the forces is reoriented so that it acts along the joint interface. Approximately 3 mL of mucus with a neutral pH spread over the surface. Biorelated Polymers and Gels.
Functionalized mucoadhesive polymers, dryg as polycarbophil, hyaluronan, and amberlite resin, have been developed and the characterization and safety aspects of nasal drug products extensively studied.
Through the transmission of a delievry signal, this specific bond can result not only in bioadhesion but also in cellular internalization by different lysosomal and non-lysosomal mechanisms Lehr, Rate controlled rectal drug delivery in man with a hydrogel preparation. Quantitative and qualitative techniques are still treated separately.
It is best applied to liquid or low-viscosity bioadhesives.
For drug delivery purposes, the term bioadhesion implies attachment of a drug carrier system to a specified biological location. The in vitro and ex vivo tests most prevalent in the literature are reported below. The authors concluded that short application times of TBO-containing mucoadhesive patches should allow the treatment of recently acquired oropharyngeal candidiasis, caused solely by planktonic cells.
The first study presenting the use of a mucoadhesive material was conducted by Nagai, and proposed an improved treatment for stomatitis by using adhesive tablets.
In vivo aspects of mucoadhesive testing have recently been reported to monitor the mucoadhesion on tissue surface such as the GIT or the buccal cavity. Park H, Robinson Mkcoadhesive. The science of adhesion I.