TITLE:
Development of Fine Poly(D,L-Lactic-Co-Glycolic Acid) Particles for Hydrophilic Drug Using a Solid-in-Oil-in-Water Emulsion
AUTHORS:
Eiichi Toorisaka, Kikumi Watanabe, Makoto Hirata
KEYWORDS:
PLGA, Hydrophilic drugs, S/O/W Emulsions, Solvent Evaporation
JOURNAL NAME:
Journal of Encapsulation and Adsorption Sciences,
Vol.8 No.2,
June
4,
2018
ABSTRACT: Poly(D,L-Lactic-Co-Glycolic
Acid) (PLGA) copolymers have been extensively used as controlled-release
carriers for many hydrophilic drugs because they are non-toxic, biodegradable,
bioavailable, and biocompatible. In general, PLGA particles have been produced
by a solvent evaporation technique utilizing water-in-oil-in-water (W/O/W)
emulsions. However, W/O/W emulsions are unstable, causing the outer and inner
aqueous phases to easily fuse during particle preparation. Consequently, a
sufficient amount of drug was not encapsulated inside the particles. In this
study, we examined a new particle preparation method utilizing a
solid-in-oil-in-water (S/O/W) emulsion technique. The advantages of S/O/W
emulsions, wherein a surfactant-drug complex disperses into the oil phase, were
as follows: 1) leakage of
hydrophilic drugs from the emulsions was inhibited, and 2) facile control over the emulsion particle size.
Thus, the PLGA particles prepared by this method showed high encapsulation
efficiency of drugs and formation of fine particles of submicron size by
membrane emulsification were achieved.