title: Heterogeneous catalysis for azide-alkyne bioconjugation in solution via spin column: Attachment of dyes and saccharides to peptides and DNA.
abstract: Copper-catalyzed azide-alkyne cycloaddition (CuAAC) "click" chemistry is widely used and has demonstrated particular utility for bio-orthogonal conjugation reactions. Here we describe a one-pot, heterogeneous bioconjugation and purification method for selectively activated CuAAC. A Cu(II) precursor, with either the neutral ligand 1,10-phenanthroline-5,6-dione or the anionic ligand 4,7-diphenyl-1,10-phenanthroline-disulfonic acid, is converted to the active Cu(I) species within an ion-exchange matrix using zinc amalgam as the reducing agent. The Cu(I) complexes are then layered on top of a size-exclusion matrix within a commercial microcentrifuge spin column; passing a mixture of an ethynyl-labeled biomolecule and an azide-bearing ligand through the column results in clean and efficient coupling. The methodology is demonstrated by glycosylating a DNA oligonucleotide as well as by labeling a membrane-penetrating peptide (octa-arginine) with a coumarin dye.
authors.affiliation: Department of Chemistry, Occidental College, Los Angeles, CA.
authors.forename: Jeremy
authors.initials: J
authors.lastname: Kallick
authors.affiliation: Department of Chemistry, Occidental College, Los Angeles, CA.
authors.forename: Sarah
authors.initials: S
authors.lastname: Harris
authors.affiliation: Department of Chemistry, Occidental College, Los Angeles, CA.
authors.forename: Andrew K
authors.initials: AK
authors.lastname: Udit
authors.affiliation: Department of Chemistry, Occidental College, Los Angeles, CA.
authors.forename: Michael G
authors.initials: MG
authors.lastname: Hill
mesh_terms: D000480:Alkynes / Q000737:chemistry*; D001386:Azides / Q000737:chemistry*; D002384:Catalysis; D002851:Chromatography, High Pressure Liquid; D057930:Click Chemistry / Q000379:methods*; D004396:Coloring Agents / Q000737:chemistry*; D003300:Copper; D004247:DNA / Q000737:chemistry; D006031:Glycosylation; D013058:Mass Spectrometry
chemical_list: D000480:Alkynes; D001386:Azides; D004396:Coloring Agents; D003300:Copper; D004247:DNA
keywords: DNA glycosylation; bioconjugation; cell-penetrating peptide; heterogeneous click conjugation