Physicochemical characteristics of pH-sensitive poly(L-histidine)-b-poly(ethylene glycol)/poly(L-lactide)-b-poly(ethylene glycol) mixed micelles.

ABSTRACT: A novel pH-sensitive polymeric micellar system composed of poly(L-histidine)-b-poly(ethylene glycol) and poly(L-lactide)-b-poly(ethylene glycol) block copolymers was studied by dynamic/static light scattering, spectrofluorimetry and differential scanning calorimetry. The mixed micelles displayed ultra Ph Sensitivity Which Could Be Tuned By Varying The Mixing Ratio Of The Two Polymers. In Particular, Mixed Micelles Composed Of 25 Wt.% Poly(L-lactide)-b-poly(ethylene glycol) exhibited desirable pH dependency which could be used as a drug delivery system that selectively targeted the extracellular pH of acidic solid tumors. Micelles were quite stable from pH 7.4 to 7.0 but underwent a two-stage destabilization as pH decreased further. A significant increase in size and aggregation number was

SUBMITTER: Yin H 

PROVIDER: S-EPMC2276666 | biostudies-literature | 2008 Mar

REPOSITORIES: biostudies-literature