title: Cavity-containing supramolecular gels as a crystallization tool for hydrophobic pharmaceuticals.
abstract: We present two approaches to low-molecular-weight supramolecular gels bearing hydrophobic cavities based on calixarene-containing building blocks. Gels are formed by a calixarene based tetrahydrazide gelator or a co-gel of a calixarene diammonium salt and a bis-crown ether. The calixarene hydrophobic cavity enables the complexation of hydrophobic drug molecules in a generic fashion thus providing an anchor site on the surface of the gel fibre to initiate drug crystal nucleation and growth. This technique potentially represents a route to growth of hard-to-nucleate polymorphic modifications. The co-gel comprising two components holding together by non-covalent ammonium-crown ether interaction can be easily switched back to the sol state by adding competitive binding cations.
authors.affiliation: Freie Universität Berlin, Takustr. 3, 14195 Berlin, Germany.
authors.forename: Lena
authors.initials: L
authors.lastname: Kaufmann
authors.affiliation: Durham University, South Road, DH1 3LE, UK. jon.steed@durham.ac.uk.
authors.forename: Stuart R
authors.initials: SR
authors.lastname: Kennedy
authors.affiliation: Durham University, South Road, DH1 3LE, UK. jon.steed@durham.ac.uk.
authors.forename: Christopher D
authors.initials: CD
authors.lastname: Jones
authors.affiliation: Durham University, South Road, DH1 3LE, UK. jon.steed@durham.ac.uk.
authors.forename: Jonathan W
authors.initials: JW
authors.lastname: Steed
mesh_terms: D047250:Calixarenes / Q000737:chemistry*; D002626:Chemistry, Pharmaceutical / Q000379:methods*; D003460:Crystallization; D018360:Crystallography, X-Ray; D005782:Gels; D057927:Hydrophobic and Hydrophilic Interactions
chemical_list: D005782:Gels; D047250:Calixarenes