Synthesis of highly water-soluble fluorescent conjugated glycopoly(p-phenylene)s for lectin and Escherichia coli
Document Type
Article
Publication Date
9-1-2006
Abstract
Two facile, convenient, and versatile synthetic approaches are used to covalently attach carbohydrate residues to conjugated poly(p-phenylene)s (PPPs) for highly water-soluble PPPs bearing α-mannopyranosyl and β-glucopyranosyl pendants (polymers A and B), which highly fluoresce in phosphate buffer (pH 7.0). The post-polymerization functionalization approach is to treat bromo-bearing PPP (polymer 1) with 1-thiolethyl-α-D-mannose tetraacetate or 1-thiol-β-D-glucose tetraacetate in THF solution in the presence of K2CO3 at room temperature through formation of thioether bridges, affording polymer 2a or 2b. The prepolymerization functionalization approach is to polymerize a well-defined sugar-carrying monomer, affording polymer 2a. Polymers 2a and 2b were deacetylated under Zemplén conditions in methanol and methylene chloride containing sodium methoxide, affording polymers A and B, respectively. The multivalent display of carbohydrates on the fluorescent conjugated glycopolymer overcomes the characteristic low binding affinity of the individual carbohydrates to their receptor proteins. Titration of concanavalin A (Con A) to α-mannose-bearing polymer A resulted in significant fluorescent quenching of the polymer with Stern-Volmer quenching constant of 4.5 × 107. Incubation of polymer A with Escherichia coli (E. coli) lead to formation of fluorescently stained bacterial clusters. β-Glucose-bearing polymer B displayed no response to Con A and E. coli. © 2006 American Chemical Society.
Publication Title
Biomacromolecules
Recommended Citation
Xue, C.,
Jog, S.,
Murphy, P.,
&
Liu, H.
(2006).
Synthesis of highly water-soluble fluorescent conjugated glycopoly(p-phenylene)s for lectin and Escherichia coli.
Biomacromolecules,
7(9), 2470-2474.
http://doi.org/10.1021/bm0604404
Retrieved from: https://digitalcommons.mtu.edu/michigantech-p/7879