title: Temperature-sensitive transitions below LCST in amphiphilic dendritic assemblies: host-guest implications.
abstract: Oligo(ethylene glycol)-decorated supramolecular assemblies have been of great interest due to their charge-neutral character and thus their propensity to avoid nonspecific interactions. These systems are known to exhibit a macroscopic temperature-sensitive transition, where the assembly phase-separates from the aqueous phase at higher temperatures. While this so-called lower critical solution temperature (LCST) behavior has been well-studied, there have been no studies on the fate of these supramolecular assemblies below this transition temperature. The work here brings to light the presence of a second, sub-LCST transition, observed well below the LCST of oligo(ethylene glycol) (OEG)-based dendrons, where the host-guest properties of the assembly are significantly altered. This sub-LCST transition is accompanied by changes in the guest encapsulation stability and dynamics of host exchange.
authors.affiliation: Department of Chemistry, University of Massachusetts, Amherst, Massachusetts 01003, USA.
authors.forename: Jack M
authors.initials: JM
authors.lastname: Fuller
authors.forename: Krishna R
authors.initials: KR
authors.lastname: Raghupathi
authors.forename: Rajasekhar R
authors.initials: RR
authors.lastname: Ramireddy
authors.forename: Ayyagari V
authors.initials: AV
authors.lastname: Subrahmanyam
authors.forename: Volkan
authors.initials: V
authors.lastname: Yesilyurt
authors.forename: S
authors.initials: S
authors.lastname: Thayumanavan
mesh_terms: D003692:Delayed-Action Preparations / Q000737:chemistry*; D019855:Ethylene Glycol / Q000737:chemistry*; D044367:Phase Transition; D044366:Transition Temperature
chemical_list: D003692:Delayed-Action Preparations; D019855:Ethylene Glycol