Polymer nanoparticles based on pyrene-functionalized poly(acrylic acid) for controlled release under photo and pH stimulation.
A novel photo and pH-responsive amphiphilic pyrene-functionalized polymer is synthesized by the esterification reaction between poly(acryloyl chloride) and pyrenemethanol and subsequent hydrolysis of the unreacted acylchloride groups. This random copolymer consists of hydrophobic pyrene-containing acrylate units and hydrophilic acrylic acid units, which can self-assemble into nanoparticles in water. Under UV irradiation, the nanoparticles can be disrupted with decreasing particle number resulted from the photolysis of pyrenylmethyl esters, where the hydrophobic segments are converted to hydrophilic acrylic acids; at low pH, the acrylic acid segments are protonated and collapsed, thus the nanoparticles will be shrunk and aggregated; at high pH, the nanoparticles change to fractal structures owing to the aggregation of partially dissociated nanoparticles and the subsequent structural reorganization of the clusters. The controlled release of Nile Red from the nanoparticles stimulated by photo and pH separately and synergistically is demonstrated. The nanoparticles self-assembled from the dual-stimuli-sensitive polymer can be used as a new nanocarrier and find their applications in delivery system.
School of Materials Science and Engineering, University of Science and Technology Beijing, Beijing, 100083, China.
Ning
N
Feng
Jie
J
Dong
Guoxiang
G
Han
Guojie
G
Wang
D000180:Acrylic Resins / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D015394:Molecular Structure; D053758:Nanoparticles / Q000737:chemistry*; D010316:Particle Size; D055668:Photochemical Processes; D011721:Pyrenes / Q000737:chemistry*; D013499:Surface Properties
D000180:Acrylic Resins; D011721:Pyrenes; C006903:carbopol 940; C030984:pyrene
colloids; nanoparticles; nanotechnology; self-assembly; stimuli-sensitive polymers