title: Influence of binary microgel phase behavior on the assembly of multi-functional raspberry-structured microgel heteroaggregates.
abstract: We investigate the influence of microgel composition on phase behavior of binary microgel dispersions using poly(N-isopropylacrylamide) microgels cross-linked with 5 mol% and 1 mol% N,N'-methylenebis(acrylamide), or poly(N-isopropylmethacrylamide) microgels cross-linked with 5 mol% N,N'-methylenebis(acrylamide). We then explore the dispersion phase behavior in the context of microgel deposition at a planar interface. These results are then compared to the observed assembly of microgels at curved interfaces, in the form of raspberry-like patchy particles (RLPPs) consisting of a polystyrene core surrounded by a (two-component) microgel shell. Results suggest that microgel composition has a large influence on the ability of binary dispersions to coat planar and curved interfaces. In particular, we demonstrate that binary dispersions of microgels containing higher cross-linker content exhibit decreased packing densities that are very pronounced at a curved interface. To enhance packing density we also explore the use of a two-step coating process to fabricate RLPPs with enhanced control over topography. Development of these complex vehicles is potentially beneficial in the modulation of biological systems where spatial and temporal presentation of molecules can have a large influence on cellular behavior.
authors.affiliation: School of Materials Science and Engineering, Georgia Institute of Technology, Atlanta, GA 30332, USA; Petit Institute for Biosciences and Bioengineering, Georgia Institute of Technology, Atlanta, GA 30332, USA. Electronic address: ssaxena30@gatech.edu.
authors.forename: Shalini
authors.initials: S
authors.lastname: Saxena
authors.affiliation: Petit Institute for Biosciences and Bioengineering, Georgia Institute of Technology, Atlanta, GA 30332, USA; Schmid College of Science and Technology, Chapman University, Orange, CA 92866, USA. Electronic address: lyon@chapman.edu.
authors.forename: L Andrew
authors.initials: LA
authors.lastname: Lyon
mesh_terms: D000178:Acrylamides / Q000737:chemistry*; D000180:Acrylic Resins / Q000737:chemistry*; D003432:Cross-Linking Reagents / Q000737:chemistry*; D016503:Drug Delivery Systems; D005782:Gels; D010316:Particle Size; D044367:Phase Transition; D011137:Polystyrenes / Q000737:chemistry; D013499:Surface Properties; D013696:Temperature
chemical_list: D000178:Acrylamides; D000180:Acrylic Resins; D003432:Cross-Linking Reagents; D005782:Gels; D011137:Polystyrenes; C052970:poly-N-isopropylacrylamide; C021221:N,N'-methylenebisacrylamide
keywords: Heteroaggregation; Microgel phase behavior; Multi-functional delivery vehicles