title: Amphiphilic calixresorcinarene associates as effective solubilizing agents for hydrophobic organic acids: construction of nano-aggregates.
abstract: Here we represent the first example of the formation of mixed nanoscale associates, constructed from amphiphilic calixresorcinarenes and hydrophobic carboxylic acids including drugs. The amidoamino-calixresorcinarene self-associates effectively solubilize hydrophobic carboxylic acids - drugs such as naproxen, ibuprofen, ursodeoxycholic acid and aliphatic dodecanoic acid - with the formation of the mixed aggregates with the macrocycle/substrate stoichiometry from 1/1 to 1/7. The ionization of organic acids and the peripheral nitrogen atoms of the macrocycles with the subsequent inclusion of hydrophobic acids into the macrocycle self-associates is the driving force of solubilization. In some cases, this leads to the co-assembly of the macrocycle polydisperse associates into supramolecular monodisperse nanoparticles with the diameter of about 100 nm. The efficiency of drug loading into the nanoparticles is up to 45% and depends on the structure of organic acid. The dissociation of the mixed aggregates and release of organic acid are attained by decreasing pH.
authors.affiliation: A. E. Arbuzov Institute of Organic and Physical Chemistry Kazan Scientific Center, Russian Academy of Science, Arbuzov str. 8, 420088 Kazan, Russian Federation. moroz@iopc.ru.
authors.forename: Ju E
authors.initials: JE
authors.lastname: Morozova
authors.forename: V V
authors.initials: VV
authors.lastname: Syakaev
authors.forename: E Kh
authors.initials: EKh
authors.lastname: Kazakova
authors.forename: Ya V
authors.initials: YV
authors.lastname: Shalaeva
authors.forename: I R
authors.initials: IR
authors.lastname: Nizameev
authors.forename: M K
authors.initials: MK
authors.lastname: Kadirov
authors.forename: A D
authors.initials: AD
authors.lastname: Voloshina
authors.forename: V V
authors.initials: VV
authors.lastname: Zobov
authors.forename: A I
authors.initials: AI
authors.lastname: Konovalov