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Ekaterina V. Popova, Victoria E. Tikhomirova, Olga V. Beznos, Natalia B. Chesnokova, Yuri V. Grigoriev, Olga A. Kost
Chitosan
nanoparticles – the drug delivery system to the anterior segment of the eye
Abstract
Abstract. The effectiveness of drug penetration into the inner tissues of the
eye is significantly limited by the barrier effect of the cornea and by the
washing out of a drug with tear fluid. To increase the bioavailability of the
drug, it was proposed to include the drug in chitosan particles formed by two
types of chitosan – 5 kDa chitosan and 72 kDa glycol-chitosan. Chitosan
particles with incorporated angiotensin-converting enzyme inhibitor
enalaprilat, capable to reduce intraocular pressure, were characterized by
dynamic light scattering and scanning electron microscopy. Particles formed by
5 kDa chitosan had an average hydrodynamic diameter of 85–125 nm and a positive
ζ-potential of +21±3 mV, while particles formed by
72 kDa glycol-chitosan were 440–480 nm by size and had ζ-potential of +10±2 mV. The percentage of inclusion of enalaprilat
in chitosan particles was 25% and 40%, respectively. In vivo experiments
have shown that the inclusion of the drug in chitosan particles increased the
retention time of enalaprilat in the lacrimal fluid of rabbits.
Key words: mucoadhesiveness, chitosan, angiotensin-converting enzyme inhibitor,
intraocular pressure, delivery to the eye, lacrimal fluid
Copyright (C) Chemistry Dept., Moscow State University, 2002
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