Probing single molecule interactions by AFM using bio-functionalized dendritips

Eric Jauvert (1, 2, 3) , Etienne Dague (1, 3) , Marjorie Severac (4) , Laurence Ressier (2) , Anne-Marie Caminade (4) , Jean Pierre Majoral (4) , Emmanuelle Trévisiol (5, 3)

1 LAAS-NBS - Équipe NanoBioSystèmes
2 LPCNO - Laboratoire de physique et chimie des nano-objets
3 ITAV - Institut des Technologies Avancées en sciences du Vivant
4 LCC - Laboratoire de chimie de coordination
5 LISBP - Laboratoire d'Ingénierie des Systèmes Biologiques et des Procédés

A new strategy for AFM (atomic force microscopy) tip functionalization based on the use of aldehyde-phosphorus dendrimers for the immobilization of biomolecules such as proteins (e.g. antibodies) is presented. Firstly functionalized with amino groups, the tips are reacted with dendrimers leading to dendrimer-activated tips (so-called dendritips). Free aldehyde functions on the dendrimer are therefore available to react with amino-functions present on every protein and many biomolecules. Using biofunctionalized-dendritip, single molecule force interactions between glutathione-S-transferase (GST) and its cognate antibody immobilized on dendritips (67 +/- 11 pN for single interaction) were probed by AFM spectroscopy. The specificity of our measurements was demonstrated by performing blocking tests resulting in the loss of interactions. (C) 2012 Elsevier B.V. All rights reserved.

Mots clés: SPECTROSCOPY; GLASS SLIDES; ATOMIC-FORCE MICROSCOPY; RECOGNITION EVENTS; Phosphorus dendrimers; Antigen/antibody interaction; Molecular recognition; Single molecule force spectroscopy (SMFS); TIPS; DNA; CELLS; ADHESION; AFM tip functionalization; ANTIBODIES; LOCALIZATION

Domaines: Sciences du Vivant [q-bio]

Eric Jauvert, Etienne Dague, Marjorie Severac, Laurence Ressier, Anne-Marie Caminade, et al.. Probing single molecule interactions by AFM using bio-functionalized dendritips. Sensors and Actuators B: Chemical, 2012, 168, pp.436 - 441. ⟨10.1016/j.snb.2012.04.048⟩. ⟨hal-01268327⟩