PolySciTech (www.polyscitech.com) provides a wide
array of biodegradable polymers including fluorescently tagged PLGA. Recently,
PolyVivo AV008 (PLGA-FPR648 conjugate) was used as part of research in the
development of PLGA nanoparticles for oral insulin delivery. The particles were
coated with a chitosan based shell to impart mucoadhesion to the particles for
insulin delivery. Use of AV008 made the particles visible under microscopy so
that their uptake in Caco-2 cells could be tracked more easily to determine
nanoparticle fate. Read more: Sheng, Jianyong, Limei Han, Jing Qin, Ge Ru,
Ruixiang Li, Lihong Wu, Dongqi Cui, Pei Yang, Yuwei He, and Jianxin Wang.
"N-trimethyl Chitosan Chloride-Coated PLGA Nanoparticles Overcoming
Multiple Barriers to Oral Insulin Absorption." ACS Applied Materials &
Interfaces (2015). http://pubs.acs.org/doi/abs/10.1021/acsami.5b03555
“Abstract: Although
several strategies have been applied for oral insulin delivery to improve
insulin bioavailability, little success has been achieved. To overcome multiple
barriers to oral insulin absorption simultaneously, insulin-loaded N-trimethyl
chitosan chloride (TMC)-coated polylactide-co-glycoside (PLGA) nanoparticles
(Ins TMC-PLGA NPs) were formulated in our study. The Ins TMC-PLGA NPs were
prepared using the double-emulsion solvent evaporation method and were characterized
to determine their size (247.6±7.2 nm), zeta potential (45.2±4.6 mV),
insulin-loading capacity (7.8±0.5%) and encapsulation efficiency (47.0±2.9%).
The stability and insulin release of the nanoparticles in enzyme-containing
simulated gastrointestinal fluids suggested that the TMC-PLGA NPs could
partially protect insulin from enzymatic degradation. Compared with unmodified
PLGA NPs, the positively charged TMC-PLGA NPs could improve the mucus
penetration of insulin in mucus-secreting HT29-MTX cells, the cellular uptake
of insulin via clathrin- or adsorption-mediated endocytosis in Caco-2 cells,
and the permeation of insulin across a Caco-2 cell monolayer through tight
junction opening. After oral administration in mice, the TMC-PLGA NPs moved
more slowly through the gastrointestinal tract compared with unmodified PLGA
NPs, indicating the mucoadhesive property of the nanoparticles after TMC
coating. Additionally, in pharmacological studies in diabetic rats, orally
administered Ins TMC-PLGA NPs produced a stronger hypoglycemic effect, with
2-fold higher relative pharmacological availability compared with unmodified
NPs. In conclusion, oral insulin absorption is improved by TMC-PLGA NPs with
the multiple absorption barriers overcome simultaneously. TMC-PLGA NPs may be a
promising drug delivery system for oral administration of macromolecular
therapeutics.”
No comments:
Post a Comment