Synthesis, spectroscopic, and analyte-responsive behavior of a polymerizable naphthalimide-based carboxylate probe and molecularly imprinted polymers prepared thereof.
A naphthalimide-based fluorescent indicator monomer 1 for the integration into chromo- and fluorogenic molecularly imprinted polymers (MIPs) was synthesized and characterized. The monomer was equipped with a urea binding site to respond to carboxylate-containing guests with absorption and fluorescence changes, namely a bathochromic shift in absorption and fluorescence quenching. Detailed spectroscopic analyses of the title compound and various models revealed the signaling mechanism. Titration studies employing benzoate and Z-L-phenylalanine (Z-L-Phe) suggest that indicator monomers such as the title compound undergo a mixture of deprotonation and complex formation in the presence of benzoate but yield hydrogen-bonded complexes, which are desirable for the molecular imprinting process, with weakly basic guests like Z-l-Phe. Compound 1 could be successfully employed in the synthesis of monolithic and thin-film MIPs against Z-L-Phe, Z-L-glutamic acid, and penicillin G. Chromatographic assessment of the selectivity features of the monoliths revealed enantioselective discrimination and clear imprinting effects. Immobilized on glass coverslips, the thin-film MIPs of 1 displayed a clear signaling behavior with a pronounced enantioselective fluorescence quenching dependence and a promising discrimination against cross-analytes.
Institute of Environmental Research, Faculty of Chemistry, Technical University of Dortmund, Otto-Hahn Strasse 6, D-44221 Dortmund, Germany.
Ricarda
R
Wagner
Wei
W
Wan
Mustafa
M
Biyikal
Elena
E
Benito-Peña
María Cruz
MC
Moreno-Bondi
Issam
I
Lazraq
Knut
K
Rurack
Börje
B
Sellergren
D005453:Fluorescence; D018698:Glutamic Acid / Q000737:chemistry*; D006860:Hydrogen Bonding; D007202:Indicators and Reagents; D054802:Molecular Imprinting; D015335:Molecular Probes / Q000737:chemistry*; D015394:Molecular Structure; D053644:Naphthalimides / Q000138:chemical synthesis* / Q000737:chemistry*; D010649:Phenylalanine / Q000737:chemistry*; D058105:Polymerization; D011108:Polymers / Q000138:chemical synthesis* / Q000737:chemistry*
D007202:Indicators and Reagents; D015335:Molecular Probes; D053644:Naphthalimides; D011108:Polymers; D018698:Glutamic Acid; D010649:Phenylalanine