title: Temperature sensitivity and drug encapsulation of star-shaped amphiphilic block copolymer based on dendritic poly(ether-amide).
abstract: The star-shaped amphiphilic block copolymer (DPEA-PCL-PNIPAAms) with different PCL block lengths was prepared through ring opening polymerization of epsilon-caprolactone (CL) initiated by hydroxyl end-capped dendritic poly(ether-amide) (DPEA-OH), and then coupling with carboxyl end-capped linear poly(N-isopropylacrylamide) (PNIPAAm-COOH) via an esterification process. The molecular structure was characterized by FT-IR, (1)H NMR, and GPC analysis. As the copolymer dissolved in water, the core-shell structural nanoparticle was formed as a micelle. The fluorescence, (1)H NMR, and dynamic light scattering (DLS) techniques were utilized to confirm the formation of micelles. The optical transmittance and US-DSC measurements demonstrated that the micelles performed the reversible dispersion/aggregation behavior in response to temperature through the outer PNIPAAm polymer shell. The micelles loaded with daidzein showed a very rapid drug release speed at temperatures above the lower critical solution temperature (LCST) due to the temperature-induced structural change of the polymeric micelles.
authors.affiliation: Department of Polymer Science and Engineering, University of Science and Technology of China, Hefei, Anhui 230026, People's Republic of China.
authors.forename: Zhu
authors.initials: Z
authors.lastname: Yang
authors.forename: Jianda
authors.initials: J
authors.lastname: Xie
authors.forename: Wei
authors.initials: W
authors.lastname: Zhou
authors.forename: Wenfang
authors.initials: W
authors.lastname: Shi
mesh_terms: D000178:Acrylamides / Q000138:chemical synthesis / Q000737:chemistry*; D000180:Acrylic Resins; D002152:Calorimetry, Differential Scanning; D002208:Caproates / Q000138:chemical synthesis / Q000737:chemistry*; D002850:Chromatography, Gel; D050091:Dendrimers / Q000138:chemical synthesis / Q000737:chemistry*; D004337:Drug Carriers / Q000737:chemistry*; D057927:Hydrophobic and Hydrophilic Interactions; D007529:Isoflavones / Q000737:chemistry / Q000494:pharmacology*; D007783:Lactones / Q000138:chemical synthesis / Q000737:chemistry*; D009682:Magnetic Resonance Spectroscopy; D008823:Micelles; D053758:Nanoparticles / Q000737:chemistry; D010316:Particle Size; D044367:Phase Transition / Q000187:drug effects; D011108:Polymers / Q000138:chemical synthesis / Q000737:chemistry*; D011721:Pyrenes / Q000737:chemistry; D012996:Solutions; D013050:Spectrometry, Fluorescence; D017550:Spectroscopy, Fourier Transform Infrared; D013696:Temperature
chemical_list: D000178:Acrylamides; D000180:Acrylic Resins; D002208:Caproates; D050091:Dendrimers; D004337:Drug Carriers; D007529:Isoflavones; D007783:Lactones; D008823:Micelles; D011108:Polymers; D011721:Pyrenes; D012996:Solutions; C052970:poly-N-isopropylacrylamide; C121056:caprolactone; C004742:daidzein; C030984:pyrene