Overcoming the aggregation problem: a new type of fluorescent ligand for ConA-based glucose sensing

Brian M. Cummins, Mingchien Li, Andrea K. Locke, David J.S. Birch, Gyula Vigh, Gerard L. Cote

Research output: Contribution to journal › Article

10 Citations (Scopus)

Abstract

Competitive binding assays based on the lectin Concanavalin A (ConA) have displayed significant potential to serve in continuous glucose monitoring applications. However, to date, this type of fluorescent, affinity-based assay has yet to show the stable, glucose predictive capabilities that are required for such an application. This instability has been associated with the extensive crosslinking between traditionally-used fluorescent ligands (presenting multiple low-affinity moieties) and ConA (presenting multiple binding sites) in free solution. The work herein introduces the design and synthesis of a new type of fluorescent ligand that can avoid this aggregation and allow the assay to be sensitive across the physiologically relevant glucose concentration range. This fluorescent ligand (APTS-MT) presents a single high-affinity trimannose moiety that is recognized by ConA’s full binding site and a fluorophore that can effectively track the ligand’s equilibrium binding via fluorescent anisotropy. This is confirmed by comparing its measured fluorescent lifetime to experimentally-determined rotational correlation lifetimes of the free and bound populations. Using an assay comprised of 200 nM APTS-MT and 1 μM ConA, the fluorescence anisotropy capably tracks the concentration of monosaccharides that are known to bind to ConA’s primary binding site, and the assay displays a MARD of 6.5% across physiologically relevant glucose concentrations. Ultimately, this rationally-designed fluorescent ligand can facilitate the realization of the full potential of ConA-based glucose sensing assays and provide the basis for a new set of competing ligands to be paired with ConA.
LanguageEnglish
Pages53-60
Number of pages8
JournalBiosensors and Bioelectronics
Volume63
Early online date11 Jul 2014
DOIs
Publication statusPublished - 15 Jan 2015

Fingerprint

Concanavalin A
Glucose
Assays
Agglomeration
Ligands
Binding sites
Binding Sites
Anisotropy
Fluorophores
Fluorescence Polarization
Competitive Binding
Monosaccharides
Crosslinking
Lectins
Fluorescence
Monitoring
Population

Keywords

  • affinity
  • glucose sensing
  • competitive binding
  • fluorescence anisotropy
  • concanavalin A

Cite this

Cummins, Brian M. ; Li, Mingchien ; Locke, Andrea K. ; Birch, David J.S. ; Vigh, Gyula ; Cote, Gerard L. / Overcoming the aggregation problem : a new type of fluorescent ligand for ConA-based glucose sensing. In: Biosensors and Bioelectronics. 2015 ; Vol. 63. pp. 53-60.
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abstract = "Competitive binding assays based on the lectin Concanavalin A (ConA) have displayed significant potential to serve in continuous glucose monitoring applications. However, to date, this type of fluorescent, affinity-based assay has yet to show the stable, glucose predictive capabilities that are required for such an application. This instability has been associated with the extensive crosslinking between traditionally-used fluorescent ligands (presenting multiple low-affinity moieties) and ConA (presenting multiple binding sites) in free solution. The work herein introduces the design and synthesis of a new type of fluorescent ligand that can avoid this aggregation and allow the assay to be sensitive across the physiologically relevant glucose concentration range. This fluorescent ligand (APTS-MT) presents a single high-affinity trimannose moiety that is recognized by ConA’s full binding site and a fluorophore that can effectively track the ligand’s equilibrium binding via fluorescent anisotropy. This is confirmed by comparing its measured fluorescent lifetime to experimentally-determined rotational correlation lifetimes of the free and bound populations. Using an assay comprised of 200 nM APTS-MT and 1 μM ConA, the fluorescence anisotropy capably tracks the concentration of monosaccharides that are known to bind to ConA’s primary binding site, and the assay displays a MARD of 6.5{\%} across physiologically relevant glucose concentrations. Ultimately, this rationally-designed fluorescent ligand can facilitate the realization of the full potential of ConA-based glucose sensing assays and provide the basis for a new set of competing ligands to be paired with ConA.",
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Cummins, BM, Li, M, Locke, AK, Birch, DJS, Vigh, G & Cote, GL 2015, 'Overcoming the aggregation problem: a new type of fluorescent ligand for ConA-based glucose sensing' Biosensors and Bioelectronics, vol. 63, pp. 53-60. https://doi.org/10.1016/j.bios.2014.07.015

Overcoming the aggregation problem : a new type of fluorescent ligand for ConA-based glucose sensing. / Cummins, Brian M.; Li, Mingchien; Locke, Andrea K.; Birch, David J.S.; Vigh, Gyula; Cote, Gerard L.

In: Biosensors and Bioelectronics, Vol. 63, 15.01.2015, p. 53-60.

Research output: Contribution to journal › Article

TY - JOUR

T1 - Overcoming the aggregation problem

T2 - Biosensors and Bioelectronics

AU - Cummins, Brian M.

AU - Li, Mingchien

AU - Locke, Andrea K.

AU - Birch, David J.S.

AU - Vigh, Gyula

AU - Cote, Gerard L.

PY - 2015/1/15

Y1 - 2015/1/15

N2 - Competitive binding assays based on the lectin Concanavalin A (ConA) have displayed significant potential to serve in continuous glucose monitoring applications. However, to date, this type of fluorescent, affinity-based assay has yet to show the stable, glucose predictive capabilities that are required for such an application. This instability has been associated with the extensive crosslinking between traditionally-used fluorescent ligands (presenting multiple low-affinity moieties) and ConA (presenting multiple binding sites) in free solution. The work herein introduces the design and synthesis of a new type of fluorescent ligand that can avoid this aggregation and allow the assay to be sensitive across the physiologically relevant glucose concentration range. This fluorescent ligand (APTS-MT) presents a single high-affinity trimannose moiety that is recognized by ConA’s full binding site and a fluorophore that can effectively track the ligand’s equilibrium binding via fluorescent anisotropy. This is confirmed by comparing its measured fluorescent lifetime to experimentally-determined rotational correlation lifetimes of the free and bound populations. Using an assay comprised of 200 nM APTS-MT and 1 μM ConA, the fluorescence anisotropy capably tracks the concentration of monosaccharides that are known to bind to ConA’s primary binding site, and the assay displays a MARD of 6.5% across physiologically relevant glucose concentrations. Ultimately, this rationally-designed fluorescent ligand can facilitate the realization of the full potential of ConA-based glucose sensing assays and provide the basis for a new set of competing ligands to be paired with ConA.

AB - Competitive binding assays based on the lectin Concanavalin A (ConA) have displayed significant potential to serve in continuous glucose monitoring applications. However, to date, this type of fluorescent, affinity-based assay has yet to show the stable, glucose predictive capabilities that are required for such an application. This instability has been associated with the extensive crosslinking between traditionally-used fluorescent ligands (presenting multiple low-affinity moieties) and ConA (presenting multiple binding sites) in free solution. The work herein introduces the design and synthesis of a new type of fluorescent ligand that can avoid this aggregation and allow the assay to be sensitive across the physiologically relevant glucose concentration range. This fluorescent ligand (APTS-MT) presents a single high-affinity trimannose moiety that is recognized by ConA’s full binding site and a fluorophore that can effectively track the ligand’s equilibrium binding via fluorescent anisotropy. This is confirmed by comparing its measured fluorescent lifetime to experimentally-determined rotational correlation lifetimes of the free and bound populations. Using an assay comprised of 200 nM APTS-MT and 1 μM ConA, the fluorescence anisotropy capably tracks the concentration of monosaccharides that are known to bind to ConA’s primary binding site, and the assay displays a MARD of 6.5% across physiologically relevant glucose concentrations. Ultimately, this rationally-designed fluorescent ligand can facilitate the realization of the full potential of ConA-based glucose sensing assays and provide the basis for a new set of competing ligands to be paired with ConA.

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KW - competitive binding

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KW - concanavalin A

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DO - 10.1016/j.bios.2014.07.015

M3 - Article

VL - 63

SP - 53

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JO - Biosensors and Bioelectronics

JF - Biosensors and Bioelectronics

SN - 0956-5663

ER -

Cummins BM, Li M, Locke AK, Birch DJS, Vigh G, Cote GL. Overcoming the aggregation problem: a new type of fluorescent ligand for ConA-based glucose sensing. Biosensors and Bioelectronics. 2015 Jan 15;63:53-60. https://doi.org/10.1016/j.bios.2014.07.015

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