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Attaching Biological Entities to AFM Cantilevers for Molecular Recognition Studies

Published online by Cambridge University Press:  01 February 2011

W. Travis Johnson*
Affiliation:
w-travis_johnson@agilent.com, Agilent Technologies, Nanotechnology Measurements Division, 4330 W Chandler Blvd, Chandler, AZ, 85226, United States, 480 216 1465
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Abstract

Atomic force microscopy (AFM) is an important tool for high resolution studies in biophysics and mechanical studies directed at biological materials. A strong suit of AFM is its ability to measure hardness/elasticity, nonspecific adhesion or ligand-receptor interactions at the picoNewton scale. Molecular interactions are critical factors in a variety of biological phenomenon; such as the initiation, modulation and termination of DNA replication, transcription, enzyme activity, infection, immune responses, tissue generation, wound healing, cell differentiation, apotopsis and physiological responses from drugs, hormones or toxic agents. Using AFM, scientists can probe and quantify these interactions in their native, liquid environments at physiological pH or perform dynamic experiments in situ by removing or adding ions, solutes and reagents to the sample environment. Bioconjugation chemistry and surface chemistry are crucial because a selective ligand must be immobilized on the tip of an AFM probe so that the AFM can resolve the mechanical force required to separate the ligand and its target. The resulting data can be used to calculate forces of unbinding, derive rate constants and infer structural information about the binding pocket. Biomolecular recognition experiments with AFM can be greatly enhanced through the use of relatively short (~8-10 nm), heterobifunctional, elastic, polyethylene glycol (PEG) linkers to immobilize ligands. Heterobifunctional linkers are used in order to permit their sequential immobilization and bioconjugation, while minimizing undesirable polymerizations or self-conjugation. The linkers have an N-hydroxysuccinimide ester at one end to permit their attachment to aminated silicon or silicon nitride AFM probes. Other reactive functional groups, such as a biotin, maleimide, disulfide, aldehyde, or a photoreactive group reside at the opposite end of the linker to permit the direct or indirect attachment of intact antibodies, Fab fragments, peptides, nucleic acids or other biological entities. The PEG linkers are flexible, so an attached ligand has freedom to diffuse within a defined volume of space and approach the binding site in a thermodynamically favorable manner. PicoTREC, an accessory for the Agilent AFM, uses ligand-PEG modified cantilevers to generate a topography image and a recognition image of biomolecular interactions. As the modified cantilever gently oscillates at defined amplitude, it is scanned across a sample and PicoTREC converts the information derived from ligand-receptor interactions into a high resolution, nanometer-scale map. Consequently, the locations of discrete molecular interactions can be easily determined and compared with a topography image of the sample.

Type
Research Article
Copyright
Copyright © Materials Research Society 2008

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References

1. Chtcheglova, , L A PhD Theiss, École Polytechnique Fédérale De Lausanne, Université Strasbourg I, France, (2004)Google Scholar
2. Lee, et al. Science 266 (1994) 771773 Google Scholar
3. Lin, et al. Emerging Information Technology Conference Proceedings, IEEE Aug. (2005)Google Scholar
4. Sekiguchi, et al. Biophysical Journal 85 (2003) 484490 Google Scholar
5. Vinckier, et al. Biophysical Journal 74 (1998) 32563263 Google Scholar
6. Lehenkari, et al. Biochemical and Biophysical Research Communications 259, (1999) 645650 Google Scholar
7. Wojcikiewicz, et al. Biol. Proced. Online 6(1) (2004) 19 Google Scholar
8. Riener, et al. Analytica Chimica Acta 479 (2003) 5975 Google Scholar
9. Allison, et al. Curr. Opinion Biotechn. 13 (2002) 4751 Google Scholar
10. Noy, et al. Annu. Rev. Mater. Sci. 27 (1997). 381421 Google Scholar
11. P, Hinterdorfer Handbook of Nanotechnology (Bushan, B, Ed), Springer Verlag (2004) 475494 Google Scholar
12. Ebner, et al. ChemPhysChem 6 (2005) 897900 Google Scholar
13. Kienberger, et al. BIOforum Europe 6 (2004a) 6668 Google Scholar
14. Kienberger, et al. Biol. Proc. Online 6 (2004b) 120128 Google Scholar
15. Lin, et al. Biophysical Journal 90 (2006) 42364238 Google Scholar
16. Marcus, et al. Biochemical and Biophysical Research Communications 342 (2006) 11231129 Google Scholar
17. Stroh, et al. Biophysical Journal 87 (2004a) 19811990 Google Scholar
18. Stroh, et al. PNAS 101(34) (2004b) 250312507 Google Scholar
19. Kienberger, et al. Single Mol. 1 (2000a) 123128 Google Scholar
20. Kienberger, et al. Single Mol. 1 (2000b) 5965 Google Scholar
21. Reiner, et al. Recent Research Developments in Bioconjugate Chemistry 1 (2002) 133149 Google Scholar
22. Hinterdorfer, et al. PNAS USA 93 (1996) 34773481 Google Scholar
23. Hinterdorfer, et al. Single Mol. 1(2) (2000) 99103 Google Scholar
24. Ratto, et al. Biophysical Journal 86 (2004) 24302437 Google Scholar
25. Ray, et al. J. Phys. Chem. B 111 (2007) 19631974 Google Scholar
26. Ros, et al. PNAS USA 95 (1998) 74027405 Google Scholar
27. Schumakovitch, et al. Biophysical Journal 82 (2002) 517521 Google Scholar
28. Schwisinger, et al. PNAS USA 97(18) (2000) 99729977 Google Scholar
29. Hinterdorfer, et al. Nanobiology 4 (1998) 177188 Google Scholar
30. Lee, et al. PNAS USA 104(23) (2007) 96099614 Google Scholar
31. Lohr, et al. Methods 41 (2007) 333341 Google Scholar
32. Vig, J R in Handbook of Semiconductor Cleaning Technology (Kern, W, Ed) Noyes Pub (1993) 233273 Google Scholar
33. Lee, et al. Israel J. Chem. 36 (1996) 8187 Google Scholar
34. Hubbard, Ed. Encyclopedia of Surface and Colloid Science Vol 1 (2002) CRC Press. P. 469 Google Scholar
35. Raab, et al. Nature Biotechnology 17 (1999) 902905 Google Scholar
36. Kamruzzahan, et al. Bioconjugate Chemistry 17(6) (2006) 14731481 Google Scholar
37. Wang, et al. Biophysical Journal 83 (2002) 36193625 Google Scholar
38. Haselgrubler, et al. Bioconjugate Chem. 6 (1995) 242248 Google Scholar
39. Ebner, et al. Bioconjugate Chem. 18 (2007) 11761184 Google Scholar
40. Hinterdorfer, et al. Colloids and Surfaces B: Biointerfaces 23 (2002) 115123 Google Scholar
41. Bash, et al. FEBS Letters 580 (2006) 47574761 Google Scholar
42. Baumgartner, et al. PNAS USA 97(8) (2000a) 40054010 Google Scholar
43. Baumgartner, et al. Single Mol. 1 (2) (2000b) 119122 Google Scholar
44. Riener, et al. Single Mol. 2(2) (2001) 127128 Google Scholar
45. Kienberger, et al. J. Mol. Biol. 347 (2005) 597606 Google Scholar
46. Nevo, et al. Nature Structural Biology 10 (2003) 553557 Google Scholar
47. Bonanni, et al. Biophysical Journal 89 (2005) 27832791 Google Scholar
48. Chtcheglova, et al. Biophysical Journal 93 (2007) L11–L13Google Scholar
49. Yoshitake, et al. Eur. J. Biochem. 101 (1979) 395399 Google Scholar
50. Wong, et al. Science 275 (1997) 820822 Google Scholar
51. VanVilet, et al. Nanotoday 1(3) (2006) 1825 Google Scholar
52. Kienberger, et al. Accounts Chemical Research 39(1) (2006) 2936 Google Scholar
53. Hinterdorfer, and Dufrene, Nature Methods 3 (2006) 347355 Google Scholar