title: Poly(ethylene oxide)-b-poly(N-isopropylacrylamide) nanoparticles with cross-linked cores as drug carriers.
abstract: Micelle-like nanoparticles that could be used as drug-delivery carriers were developed. The unique feature of these nanoparticles was that the core of poly(ethylene oxide)-b-poly(N-isopropylacrylamide) (PEO-b-PNIPAAm) micelle was lightly cross-linked with a biodegradable cross-linker, N,N-bis(acryloyl)cystamine (BAC). The nanoparticles were characterized by dynamic light scattering and fluorescence measurements. When the BAC content ranged from 0.75 wt% to 0.2 wt% of the mass of NIPAAm, the diameters of the nanoparticles were less than 150 nm. The anti-cancer drug doxorubicin (Dox) and 1,6-diphenyl-1,3,5-hexatriene (DPH) were used as fluorescent probes to study the hydrophobicity of the cores of the nanoparticles; the results showed that the cores of the nanoparticles were hydrophobic enough to sequester Dox and DPH. The nanoparticles with 0.5 wt% BAC stored at room temperature were stable up to 2 weeks, even at dilute concentrations. The degradation of BAC by reducing agent beta-mercaptoethanol was investigated, and the nanoparticles were not detectable 14 days after adding beta-mercaptoethanol.
authors.affiliation: Chemical Engineering Department, 350 Clyde Building, Brigham Young University Provo, UT 84602, USA.
authors.forename: Yi
authors.initials: Y
authors.lastname: Zeng
authors.forename: William G
authors.initials: WG
authors.lastname: Pitt
mesh_terms: D000180:Acrylic Resins / Q000737:chemistry*; D001672:Biocompatible Materials / Q000737:chemistry*; D001673:Biodegradation, Environmental; D003432:Cross-Linking Reagents / Q000494:pharmacology; D003538:Cystamine / Q000494:pharmacology; D004161:Diphenylhexatriene / Q000494:pharmacology; D004305:Dose-Response Relationship, Drug; D004317:Doxorubicin / Q000494:pharmacology*; D004337:Drug Carriers; D016503:Drug Delivery Systems; D005027:Ethylene Oxide / Q000737:chemistry; D005456:Fluorescent Dyes / Q000494:pharmacology; D008027:Light; D008623:Mercaptoethanol / Q000494:pharmacology; D008823:Micelles; D049329:Nanostructures / Q000737:chemistry*; D036103:Nanotechnology; D010316:Particle Size; D011092:Polyethylene Glycols / Q000737:chemistry*; D011108:Polymers / Q000737:chemistry; D012542:Scattering, Radiation; D013050:Spectrometry, Fluorescence; D013696:Temperature; D013997:Time Factors
chemical_list: D000180:Acrylic Resins; D001672:Biocompatible Materials; D003432:Cross-Linking Reagents; D004337:Drug Carriers; D005456:Fluorescent Dyes; D008823:Micelles; D011108:Polymers; D004161:Diphenylhexatriene; C052970:poly-N-isopropylacrylamide; D011092:Polyethylene Glycols; D008623:Mercaptoethanol; D004317:Doxorubicin; D005027:Ethylene Oxide; D003538:Cystamine