Dual-responsive crosslinked pluronic micelles as a carrier to deliver anticancer drug taxol

A dual-sensitive chemically crosslinked polymer (CCP) forming nanosized micelles bearing a pH responsive covalent benzoic-imine bond and redox sensitive disulfide is reported as an endocytosis based target delivery system to deliver the anticancer drug Taxol. The size of the micelles was 38.6 +/- 10.9 and 99.5 +/- 26.2 measuring from dynamic light scattering (DLS) before and after Taxol loading where morphology of the micelles were evaluated via transmission electron microscopy images (TEM). The Taxol loading content was 1.6% with 33.4% loading efficiency. Significant micelles stability wax was observed at normal physiological conditions by investigating the change in emission intensity for the encapsulated quantum dots (QDs). A significant amount of Taxol was released under individual stimuli within a short period of time. The CCP micelles showed non-toxic properties when applied to the A549 cell and considerable cytotoxicity has been found from the drug, loaded within the micelles. Cellular uptake of the Taxol loaded micelles was confirmed via confocal laser scanning microscopy. These biodegradable micelles may be a potential candidate in carrier based intelligent drug delivery system in order to deliver cytotoxic hydrophobic drug

Preparation of cross-linked biodegradable copolymers based polycarbanion of 3-arm PL(D)LA with brominated pluronic and stereocomplex mediated gelation behavior

We overcome rapidly dissolution properties of Pluronic hydrogels by chemical and physical crosslinking synergistic combination of gelation characteristics with polymer thermo-sensitivity. A new class of injectable sol-gel transition hydrogel was successfully prepared using biodegradable cross-linked poly(lactide)-Pluronic copolymers (PL(D)LA-Pluronic) via polycarbanion derived from enantiomeric 3-arm PLA using brominated Pluronic. The presence of enantiomeric PLA segments enables to form intermolecular stereocomplex, resulting in temperature-responsive injectable hydrogels. In contrast to the Pluronic which exhibits the temperature-dependent sol-gel transition at a concentration of 16% (w/v) or higher, the 3-arm PL(D)LA-Pluronic cross-linked stereocomplex copolymers showed much lower critical gelation concentration (∼ 10 wt%). The stereocomplex formation was examined by differential scanning calorimetry (DSC) and X-ray diffraction (XRD). The elegant design of polymeric configurations and the suitable introduction of enantiomeric properties produced a new type of copolymer that can be widely implemented as injectable hydrogels for drug delivery systems

Spiropyran-conjugated Pluronic as a dual responsive colorimetric detector

Novel spiropyran-conjugated Pluronic [polyethylene oxide (PEO)-b-polypropylene oxide (PPO)-b-polyethylene oxide (PEO)] micelles are developed as a new colorimetric detector showing photo- or thermo-switchable behavior. Facile conjugation of spiropyran to Pluronic was confirmed by 1H NMR, UVVis, and Fluorescence spectroscopy. A switchable photoluminescence is found depending on the irradiation with either UV or visible light, and temperature resulting from structural isomerization of spiropyran between spiropyran (SP) and merocyanine (MC) form. Cytotoxicity of the spiropyran-conjugated Pluronic (SP-PL) was evaluated following an MTT assay, whereas photo responsiveness of spiropyran within the micelles was determined by confocal laser scanning microscopy

Synthesis and characterization of a multi-sensitive crosslinked injectable hydrogel based on Pluronic

This paper reports the construction of a novel multi-sensitive chemically crosslinked injectable hydrogel with strong mechanical strength by modifying Pluronic F127 responsive against temperature, pH and redox potential. Crosslinked polymer between benzaldehyde grafted Pluronic (P-A) and amine end capped Pluronic having disulfide linkage (P-B) have been synthesized and characterized with 1 H NMR spectroscopy and GPC. The hydrogel under physiological conditions significantly altered sol-gel transition behaviors with much lower critical gelation concentrations and temperatures, compared to Pluronic hydrogels. The rheological characterization demonstrated that the moduli of the hydrogels were able to be tuned depending on molecular weight as well as pH, redox and temperature conditions