title: Hollow thermoresponsive microgels.
abstract: Thermoresponsive poly(N-isopropyl acrylamide) (pNIPAm) microgels possessing a hollow structure have been synthesized from core-shell nanoparticles upon oxidation of the particle core, followed by removal of the produced polymer segments by centrifugation. N,N'-(1,2-dihydroxyethylene)bisacrylamide (DHEA) is used as a cross-linker for preparing the degradable core, whereas N,N'-methylenebis(acrylamide) (BIS) is used as a cross-linker to add a nondegradable pNIPAm shell. Addition of NaIO(4) to a suspension of these particles in water leads to controlled degradation of the particle core by cleavage of the 1,2-glycol bond in DHEA. Fluorescence spectroscopy, UV/Vis spectroscopy, and photon correlation spectroscopy are used to characterize the hollow particles produced.
authors.affiliation: School of Chemistry and Biochemistry, Georgia Institute of Technology, Atlanta, GA 30332-0400, USA.
authors.forename: Satish
authors.initials: S
authors.lastname: Nayak
authors.forename: Daoji
authors.initials: D
authors.lastname: Gan
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Serpe
authors.forename: L Andrew
authors.initials: LA
authors.lastname: Lyon
mesh_terms: D020106:Acrylamide / Q000737:chemistry; D003460:Crystallization; D003687:Dehydroepiandrosterone / Q000737:chemistry; D005782:Gels / Q000737:chemistry*; D008422:Materials Testing; D053758:Nanoparticles / Q000737:chemistry*; D049329:Nanostructures; D036103:Nanotechnology / Q000295:instrumentation* / Q000379:methods*; D043942:Nanotubes; D010316:Particle Size; D011108:Polymers / Q000737:chemistry*; D013050:Spectrometry, Fluorescence; D013056:Spectrophotometry, Ultraviolet; D013499:Surface Properties; D013696:Temperature
chemical_list: D005782:Gels; D011108:Polymers; D020106:Acrylamide; D003687:Dehydroepiandrosterone