Abstract
A new approach for the specific detection and mapping of single molecule recognition is presented, based on the nonlinear elastic behavior of a single polymer chain. The process of molecular recognition between a ligand and a receptor is inherently accompanied by a decrease in the translational and rotational degrees of freedom of the two molecules. We show that a polymeric tether linked to the ligand can effectively transduce the configurational constraint imposed by molecular recognition into a measurable force, which is dominated by the entropic elasticity of the polymer. This force is specifically characterized by a strong nonlinearity when the extension of the polymer approaches its contour length. Thus, a polymer chain tethering the ligand to an oscillating cantilevered tip gives rise to a highly anharmonic motion upon ligand-receptor binding. Higher-harmonics atomic force microscopy allows us to detect this phenomenon in real time as a specific signature for the probing and mapping of single-molecule recognition.
Original language | English |
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Pages (from-to) | 11390-11398 |
Number of pages | 9 |
Journal | Journal of the American Chemical Society |
Volume | 127 |
Issue number | 32 |
DOIs | |
Publication status | Published - 17 Aug 2005 |
All Science Journal Classification (ASJC) codes
- General Chemistry
- Biochemistry
- Catalysis
- Colloid and Surface Chemistry