Background:
Micelles as drug carriers are characterized by their inherent instability due to the weak
physical interactions that facilitate the self-assembly of amphiphilic block copolymers. As one of the strong
physical interactions, the stereocomplexation between the equal molar of enantiomeric polylactides, i.e., the
poly(L-lactide) (PLLA) and poly(D-lactide) (PDLA), may be harnessed to obtain micelles with enhanced stability
and drug loading capacity and consequent sustained release.
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Aims/Methods: In this paper, stereocomplexed micelles gama-PGA-g-PLA micelles) were fabricated from the
stereocomplexation between poly(gama-glutamic acid)-graft-PLLA gama-PGA-g-PLA) and poly(gamaglutamic
acid)-graft-PDLA gama-PGA-g-PLA). These stereocomplexed micelles exhibited a lower CMC than
the corresponding enantiomeric micelles.
Result:
Furthermore, they showed higher drug loading content and drug loading efficiency in addition to more
sustained drug release profile in vitro. In vivo imaging confirmed that the DiR-encapsulated stereocomplexed
gama-PGA-g-PLA micelles can deliver anti-cancer drug to tumors with enhanced tissue penetration. Overall,
gama-PGA-g-PLA micelles exhibited greater anti-cancer effects as compared with the free drug and the stereocomplexation
may be a promising strategy for fabrication of anti-cancer drug carriers with significantly enhanced
efficacy.