title: Aminoglutethimide-imprinted xerogels in bulk and spherical formats, based on a multifunctional organo-alkoxysilane precursor.
abstract: The multifunctional alkoxysilane precursor, 2,6-bis(propyl-trimethoxysilylurelene)pyridine (DPS) was designed and synthesized, envisaging a multiple hydrogen-bond interaction in the molecular imprinting of the drug aminoglutethimide (AGT). Imprinted xerogels were obtained in bulk and spherical formats. The spherical format was achieved by pore-filling onto spherical mesoporous silica, as a straightforward technique to generate the spherical format. The bulk gels presented better selectivity for the template against its glutarimide (GLU) analogue (selectivity factor: bulk 13.4; spherical 4.6), and good capacity (bulk 5521μmol/L; spherical 2679μmol/L) and imprinting factor parameters (bulk 11.3; spherical 1.4). On the other hand, the microspherical format exhibited better dynamic properties associated to chromatographic efficiency (theoretical plates: bulk 6.8; spherical 75) and mass transfer, due mainly to the existence of a mesoporous network, lacking in the bulk material. The performance of the imprinted xerogels was not as remarkable as that of their acrylic counterparts, previously described. Overall it was demonstrated that the use of designed new "breeds" of organo-alkoxysilanes may be a strategy to achieve satisfactory imprints by the sol-gel processes. DPS may in principle be applied even more effectively to other templates bearing better-matching spatially compatible acceptor-donor-acceptor arrays.
authors.affiliation: CIQ-UP, Departamento de Química e Bioquímica, Faculdade de Ciências, Universidade do Porto, Portugal. Electronic address: porkodikathirvel@yahoo.com.
authors.forename: Porkodi
authors.initials: P
authors.lastname: Kadhirvel
authors.affiliation: CIQ-UP, Departamento de Química e Bioquímica, Faculdade de Ciências, Universidade do Porto, Portugal. Electronic address: mazenha@fc.up.pt.
authors.forename: Manuel
authors.initials: M
authors.lastname: Azenha
authors.affiliation: CIQ-UP, Departamento de Química e Bioquímica, Faculdade de Ciências, Universidade do Porto, Portugal.
authors.forename: Paula
authors.initials: P
authors.lastname: Gomes
authors.affiliation: CIQ-UP, Departamento de Química e Bioquímica, Faculdade de Ciências, Universidade do Porto, Portugal.
authors.forename: António F
authors.initials: AF
authors.lastname: Silva
authors.affiliation: INFU, Faculty of Chemistry, Technical University of Dortmund, Otto-Hahn-Str.6, D-44221, Dortmund, Germany; Department of Biomedical Sciences, Faculty of Health and Society, Malmö University, SE 20506 Malmö, Sweden.
authors.forename: Börje
authors.initials: B
authors.lastname: Sellergren
mesh_terms: D000616:Aminoglutethimide / Q000737:chemistry*; D000970:Antineoplastic Agents / Q000737:chemistry*; D005782:Gels; D006860:Hydrogen Bonding; D054802:Molecular Imprinting; D044367:Phase Transition; D011725:Pyridines / Q000737:chemistry*; D012822:Silicon Dioxide / Q000737:chemistry
chemical_list: C000608349:2,6-bis(propyl-trimethoxysilylurelene)pyridine; D000970:Antineoplastic Agents; D005782:Gels; D011725:Pyridines; D000616:Aminoglutethimide; D012822:Silicon Dioxide
keywords: Aminoglutethimide; Microspherical; Molecular imprinting; Organo-alkoxysilane; Sol–gel