Nanospheres oral delivery

Kawashima, Y., et al. 2000. Mucoadhesive DL-lactide/glycolide copolymer nanospheres coated with chitosan to improve oral delivery of elcatonin. Pharm Dev Technol 5 77. 

Thongborisute J, Tsuruta A, Takeuchi H (2008) Correlation of drug absorption level and pharmacological efficiency of oral chitosan-coated liposomal systems. Unpublished Torres-Lugo M, Garcia M, Record R, Peppas NA (2002) Physicochemical behavior and cytotoxic effects of p(methacrylic acid-g-ethylene glycol) nanospheres for oral delivery of proteins. J Control Rel 80(1-3) 197-205... 

With regard to protein oral delivery, an experiment was conducted on a pH-sensitive hydrogel polymer composed of poly[methacrylic acid-graft-poly(ethylene glycol)] (P(MAA-g-EG)) (77-80). The P(MAA-g-PEG) nanosphere system demonstrated low cytotoxicity and was capable of opening... 

Nanospheres for oral delivery Encapsulating the bioactive molecules prevents enzymatic degradation of drug which makes it an apt vehicle for oral delivery. Nanospheres for drug delivery in the brain Capability of targeting specific receptor-mediated transport system in the blood—brain barrier (BBB) makes nanospheres an ideal choice for drug delivery in the brain. For example, Polysorbate 80/LDL is capable of delivery to the brain. 

Although it appears that the majority of work with PLGA microspheres for oral delivery is directed toward vaccine administration, PLGA nanospheres have also been investigated as a potential alternate oral delivery system for cyclosporin (Sanchez et al, 1993). 

Figure 3. Schematic diagram of the fate of nanospheres following their oral delivery...

There are many issues with oral delivery of nanospheres, such as the efficiency of uptake, reproducibility, and the pathophysiologic condition of the patient (e.g. diarrhoea) that could affect the retention of orally administered nanospheres. To increase the efficacy of uptake of nanospheres by the gastrointestinal tract, investigators have been studying nanospheres which are surface modified with lectins and transferrin The receptors... 

Carino, G.P. Jacob, J.S. Mathiowitz, E. Nanosphere based oral insulin delivery. J. Control Release 2000,... 

Emulsions and suspensions are disperse systems that is, a liquid or solid phase is dispersed in an external liquid phase. While emulsions are sometimes formulated from oily drugs or nutrient oils their main function is to provide vehicles for drug delivery in which the drug is dissolved in the oil or water phase. Suspensions, on the other hand, are usually prepared from water-insoluble drugs for delivery orally or by injection, usually intramuscular injection. An increasing number of modern delivery systems are suspensions - of liposomes or of polymer or protein microspheres, nanospheres or dendrimers, hence the need to understand the formulation and stabilization of these systems. Pharmaceutical emulsions and suspensions are in the colloidal state, that is where the particles range from the nanometre size to visible (or coarse) dispersions of several micrometres. 

G. Carino, J. S. Jacob and E. Mathiowitz,. Nanosphere based oral insulin delivery. /. Control Release., 65(1-2), 261-269 (2000). 

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