Cationic imprinting of Pb(II) within composite networks based on bovine or fish chondroitin sulfate.
Imprinting chondroitin sulfate (CS)/silica composites with Pb(II) and Cu(II) cations was explored with CS of bovine and different fish species origin. The process was based on the assumption that particular arrangements of the linear CS chains in aqueous solution, induced so as to accommodate cross complexation with the cations, would be embodied into a tridimensional matrix created through an organoalkoxysilane sol-gel scheme. The presence of Cu(II) in the synthesis of the composites did not result in the production of significantly stronger Cu(II)-oriented binding arrangements, and therefore, the imprinting was not successful. Inversely, for Pb(II), the materials obtained exhibited a "memory" effect for the Pb(II) ions, expressed in the observation of stronger (13%-44%) binding as compared to the nonimprinted counterparts, and increased selectivity (1.5-2 folds) against Cd(II). The imprinting features observed were dependent on the CS source. However, it was not possible to identify, among a set of their properties (carboxylate and sulfate abundance, percent of disulfated units, 4S/6S ratio, and molecular weight), any that correlated directly with the observed imprinting features. The augmented selectivity provided by the cation-imprinting process may be advantageous in areas such as analytical separation, remediation, purification, sensing, and others, particularly in those cases where a certain cation is of special interest within a mixture of them.
CIQ-UP; Departamento de Química e Bioquímica, Faculdade de Ciências da Universidade do Porto, Porto, Portugal.
Vanessa R A
VRA
Ferreira
CIQ-UP; Departamento de Química e Bioquímica, Faculdade de Ciências da Universidade do Porto, Porto, Portugal.
Manuel A
0000-0003-3709-7478
MA
Azenha
CIQ-UP; Departamento de Química e Bioquímica, Faculdade de Ciências da Universidade do Porto, Porto, Portugal.
M Teresa
MT
Mêna
CIQ-UP; Departamento de Química e Bioquímica, Faculdade de Ciências da Universidade do Porto, Porto, Portugal.
Cosme
C
Moura
CIQ-UP; Departamento de Química e Bioquímica, Faculdade de Ciências da Universidade do Porto, Porto, Portugal.
Carlos M
CM
Pereira
Grupo de Bioquímica de Alimentos, Instituto de Investigaciones Marinas (IIM-CSIC), Vigo, Spain.
Ricardo I
RI
Pérez-Martín
Grupo de Reciclado y Valorización de Residuos (REVAL), Instituto de Investigaciones Marinas (IIM-CSIC), Vigo, Spain.
José A
JA
Vázquez
CIQ-UP; Departamento de Química e Bioquímica, Faculdade de Ciências da Universidade do Porto, Porto, Portugal.
A Fernando
AF
Silva
D000818:Animals; D002412:Cations / Q000737:chemistry; D002417:Cattle; D002809:Chondroitin Sulfates / Q000737:chemistry*; D005399:Fishes; D007854:Lead / Q000737:chemistry*; D054802:Molecular Imprinting
D002412:Cations; D007854:Lead; D002809:Chondroitin Sulfates
cation-imprinting; chondroitin sulfate; composite; lead (II); sol-gel