Spectroscopy force

AFM can be used to determine the dependence of the interaction on the probe-sample distance at a given location [85], in so-called atomic force spectroscopy (AFS). Both the 

AFS has been used in the investigation of conductivity in polymers, namely PANI and its derivatives (POEA and POMA). The degree of protonation and the conductivity vary within the PANI class, which is attributed to differences in conformation of the polymer chains and packing in a film. The mechanisms of charge conduction are still not completely understood, precisely because of the diversity of factors affecting conductivity. It is, nevertheless, widely accepted that in the PANI structure the doped molecules are not uniformly distributed, but rather agglomerated into conducting islands. In a systematic 

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Gotsmann B, Anczykowski B, Seidel C and Fuchs H 1999 Determination of tip-sample interaction forces from measured dynamic force spectroscopy curves Appl. Surf. Sc/. 140 314... 

Feldman K, Tervoort T, Smith P and Spencer N D 1998 Toward a force spectroscopy of polymer surfaces Langmuir 14 372... 

Rief, M., Oeslerhelt, F., Heymann, B. and Gaub, H.E., Single molecule force spectroscopy on polysaccharides by atomic force microscopy. Science, 275(5304), 1295-1297 (1997). 

Janshoff, A., Neitzerl, M., Oberdorfer, Y. and Fuchs, H., Force spectroscopy of molecular systems - single molecule spectroscopy of polymers and biomolecules. Angew. Chem. Int. Edn., 39(18), 3213-3237 (2000). 

More subtle effects of the dielectric constant and the applied bias can be found in the case of semiconductors and low-dimensionality systems, such as quantum wires and dots. For example, band bending due to the applied electric field can give rise to accumulation and depletion layers that change locally the electrostatic force. This force spectroscopy character has been shown by Gekhtman et al. in the case of Bi wires [38]. 

Levy R, Maaloum M. 2005. Specific molecular interactions by force spectroscopy From single bonds to collective properties. Biophys Chem 117 233-237. 

FIGURE 6.2 Diagrams of different AFM operating modes. (A) Contact mode and (B) dynamic mode for topographic imaging. (C) Force spectroscopy mode for interaction probing. Reprinted with permission from Liu and Wang (2010). 

Noy, A., Direct determination of the equilibrium unbinding potential profile for a short DNA duplex from force spectroscopy data, Appl. Phys. Lett. 2004, 85, 4792-4794... 

Hummer, G. Szabo, A., Free energy surfaces from single-molecule force spectroscopy, Acc. Chem. Res. 2005, 38, 504—513... 

Odorico, M., Teulon, J.-M., Bessou, T., Vidaud, C., Bellanger, L., Chen, S.-W., Qucmcncur, fi., Parot, P., and Pellequer, J.-L. (2007) Energy landscape of chelated uranyl Antibody interactions by dynamic force spectroscopy. Biophys. J. 93, 645-654. 

J. Kaur, K.V. Singh, A.H. Schmid, G.C. Varshney, C.R. Suri, and M. Raje, Atomic force spectroscopy-based study of antibody pesticide interactions for characterization of immunosensor surface. Biosens. Bioelectron. 20, 284—293 (2004). 

Oroudjev, E., Soares, J., Arcdiacono, S., Thompson, J. B., Fossey, S. A., and Hansma, H. G. (2002). Segmented nanofibres of spider dragline silk Atomic force microscopy and single-molecule force spectroscopy. Proc. Natl. Acad. Sci. USA 99, 6460-6465. 

Dynamic Force Spectroscopy A Fokker-Planck Approach. 

R. Merkel, P. Nassoy, A. Leung, K. Ritchie, and E. Evans Energy Landscapes of Receptor-Ligand Bonds Explored with Dynamic Force Spectroscopy. Nature 397, 50 (1999). 

Auletta T, de Jong MR, Mulder A, van Veggel FCJM, Huskens J, Reinhoudt DN, Zou S, Zapotoczny S, Schonherr H, Vancso GJ, Kuipers L. 3-Cyclodextrin host-guest complexes prohed under thermodynamic equilibrium thermodynamics and AFM force spectroscopy. J Am Chem Soc 2004 126 1577-1584. 

Gu C, Ray C, Guo S, Akhremitchev BB. Single-molecule force spectroscopy measurements of interactions between C60 fullerene molecules. J Phys Chem C 2007 111 12898-12905. 

Kersey FR, Yount WC, Craig SL. Single-molecule force spectroscopy of bimolecular reactions system homology in the mechanical activation of ligand substitution reactions. J Am Chem Soc 2006 128 3886-3887. 

Kudera M, Eschbaumer C, Gaub HE, Schubert US. Analysis of metallo-supiamolecular systems using single-molecule force spectroscopy. Adv Eunct Mater 2003 13 615-620. 

Stmnz T, Oroszlan K, Schafer R, Guntherodt H-J. D3mainic force spectroscopy of single DNA molecules. ProcNad Acad Sci USA 1999 96 11277-11282. 

Vezenov D, Zhuk A, Whitesides G, Lieber C. Chemical force spectroscopy in heterogeneous systems intermolecular interactions involving epoxy polymer, mixed monolayers, and polar solvents. J Am Chem Soc 2002 124 10578-10588. 

Fisher TE, Carrion-Vazquez M, Oberhauser AF, Li H, Marszalek PE, Fernandez JM. Single molecule force spectroscopy of modular proteins in the nervous system. Neuron 2000 27 435-446. 

Guzman DL, Roland JT, Keer H, Kong YP, Ritz T, Yee AF, Guan Z. Using computational single molecule force spectroscopy in rational design of strong, modular nanostructures for use in materials synthesis. Submitted 2007. 

Oroudjev E, Soares J, Arcdiacono S, Thompson JB, Fossey SA, Hansma HG. Segmented nanofibers of spider dragline silk atomic force microscopy and single-molecule force spectroscopy. Proc Natl Acad Sci USA 2002 99 6460-6465. 

Zou S, Schoenherr H, Vancso GJ. Force spectroscopy of quadruple H-bonded dimers by AFM dynamic bond rupture and molecular time-temperature superposition. J Am Chem Soc 2005 127 11230-11231. 

Table 3.1 Selected Examples of Supramolecular Interactions, Relevant to Supramolecular Polymers, Studied by Force Spectroscopy...

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