Rapid Colorimetric Detection of Antibody−Epitope Recognition at a Biomimetic Membrane Interface

Abstract

Biomolecular recognition of antigens and epitopes by antibodies is a fundamental event in the initiation of immune response and plays a central role in a variety of biochemical processes. Peptide binding requires, in many cases, presentation of the peptides at interfaces, such as protein surfaces, cellular membranes, and synthetic polymer surfaces. We describe a novel molecular system in which interactions between antibodies and peptide epitopes displayed at a biomimetic membrane interface can be detected through induction of visible, rapid color transitions. The colorimetric assembly consists of a phospholipid/polydiacetylene matrix anchoring a hydrophobic peptide displaying the epitope at its N-terminus. The colorimetric transitions observed in the assembly, corresponding to perturbation of the polydiacetylene framework, are induced only upon recognition of the displayed epitope by its specific antibody present in the aqueous solution. Significantly, the color changes occur after a single mixing step, without further chemical reactions or enzymatic processing. The new molecular system could be utilized for studying antigen-antibody interactions and peptide-protein recognition, epitope mapping, and rapid screening of biological and chemical libraries.

Stable Drug Delivery Systems: Peg-Polydiacetylene Liposomes.

“…The ordered form is maintained even in the PEG conjugated PDA along with the color transition properties. PEG conjugation imparts additional stability and improves the retention time of the drug for sustained release reducing the toxic side effects [20,30].…”

N-ACETYLGALACTOSAMINE BIOSENSOR BASED ON POLYDIACETYLENE NANOVESICLES: AN INDIRECTLY COLORIMETRIC RECOGNITION OF GALACTOSE-DEFICIENT IgA1

“…PCDA nanovesicles showed colorimetric response to various external stimuli such as temperature, solvents, pH and biomolecules, [19][20][21][22][23] which interacted with or disrupted the pendant side chains of the polymer. The PCDA nanovesicles exhibited dramatic blue to red color transitions.…”

Synthesis of New PCDA-Carbohydrate Derivatives

“…[1][2][3][4][5][6][7][8][9][10] It is well known that the spacially aligned monomeric diacetylene moieties undergo photo polymerization process via a 1,4-addition mechanism and form conjugated chains that give the molecule a significant color change.…”