Microparticles mucoadhesive

For bioadhesive applications, anionic polymers appear to provide the most effective balance between adhesiveness and toxicity, with carboxylic materials preferred over sulfonic polymers [400]. Polyfacrylic acid) microparticles have been identified as particularly effective bioadhesive materials [402]. Studies with poly(acrylic acid) microparticles have indicated that, while water-swollen particles exhibit good bioadhesion, dry polymer particles give no adhesion at all. In addition, adhesive strength increases as the degree of ionization of the polymer is increased [402]. Thus the expanded nature of the polymer network is important to mucoadhesion, probably via polymer interdiffusion and entanglement with mucin [403],... 

Cuna, M., Alonso, M. J., and Torres, D. Preparation and in vivo evaluation of mucoadhesive microparticles containing amoxycillin-resin complexes for drug delivery to the gastric mucosa. Eur. J. Pharm. Biopharm. 51(3) 199-205, 2001. 

The fate of nanoparticles has also been investigated in vivo. Albrecht et al. studied the in vivo mucoadhesive properties of thiomer formulations using magnetic resonance imaging and fluorescence detection (Albrecht et al. 2006). Following the hypothesis that unhydrated thiomers provide better mucoadhesion in vivo the group developed polycarbophil-cysteine microparticles loaded with fluoresceine diacetate (FDA) in Eutex capsules to maintain them in the dry... 

Microparticles and nanoparticles present some advantageous features, namely mucoadhesive properties. They have demonstrated some potential in vaginal drug delivery, particularly in the formulation of delivery systems for vaccines or peptides and proteins [160, 161], Nonetheless, these particles have to be incorporated in adequate carrier systems in order to be delivered. This task has been shown to be complex, it being hard to achieve controlled-release and steady-release profiles. 

Mikos and Peppas described the flow channel to measure the bioadhesion of polymer microparticles on mucin gels. Later Lehr et al. ° used an in situ loop model in the rat for the investigation of mucoadhesive microspheres (Fig. 3). They concluded that this approach allowed the study of the transit of particles. Another technique to study the mucoadhesive properties of microspheres is the electrobalance method, as... 

The particles demonstrated a greater swelUng and mucoadhesive properties than did uncoated microparticles. The in vitro release from the microparticles indicated that the coated microparticles resulted in more sustained release than uncoated microparticles. The in vivo oral administration demonstrated that at the same amount of 250 pg OVA, coated microparticles exhibited the highest in vivo adjuvant activity in both IgG and IgA immunogenicity. 

Wittaya-areekul, S., Kruenate, J., Prahsarn, C., 2006. Preparation and in vitro evaluation of mucoadhesive properties of alginate/chitosan microparticles containing prednisolone. International Journal of Pharmaceutics 312, 113—118. 

Deat-Laine E, Hoffart V, Garrait G, jarrige J-F, Cardot J-M, Subirade M, Beyssac E (2013). Efficacy of mucoadhesive hydrogel microparticles of whey protein and alginate for oral insulin delivery. Pharm Res, 30, 721-734. 

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