Immobilization and Interaction Strategies in DFS of Biomolecular Partners - Dynamic Force Spectroscopy and Biomolecular Recognition - page 133

4 Immobilization and

Interaction Strategies
in DFS of Biomolecular
Partners

Boris B. Akhremitchev

CONTENTS
4.1 Introduction................................................................................................... 133
4.2 Immobilization Strategies ............................................................................. 134
4.3 Physical Methods of Attaching Molecules ................................................... 136
4.4 Chemical Methods of Attaching Biomolecules............................................ 138
4.4.1 Chemical Reactions to Immobilize Biomolecules ........................... 138
4.4.2 Chemical Modification of Substrates ............................................... 140
4.4.2.1 Functionalization of Gold Surfaces.................................. 141
4.4.2.2 Functionalization of Surfaces Displaying Silanol
Groups .............................................................................. 142
4.4.2.3 Immobilization of Molecules to Functionalized
Surfaces ............................................................................ 145
4.4.2.4 Example of Chemical Immobilization on Gold
Surfaces ............................................................................ 146
4.4.2.5 Example of Chemical Immobilization Using Silanol
Chemistry ......................................................................... 150
4.5 Multiple Interactions between Immobilized Molecules ............................... 151
4.5.1 Probability of Single-Molecule Events ........................................... 153
4.5.2 Effects of Multiple Interactions on Measured Data ........................ 154
4.6 Conclusion .................................................................................................... 156
References.............................................................................................................. 156

4.1 INTRODUCTION
In dynamic force spectroscopy (DFS), mechanical forces are applied to intermolecular
bond understudy to characterize strength of biomolecular recognition and extract
kinetic parameters of bond dissociation. To perform such measurements, interacting
partners should be attached to the opposing surfaces of atomic force spectroscopy
(AFM) probe and the substrate. Thus, successful immobilization is vital for obtaining

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