Molecular conformation in oligo(ethylene glycol)-terminated self-assembled monolayers on gold and silver surfaces determines their ability to resist protein adsorption

Journal of Physical Chemistry B

Volumn 102, Issue 2, 1998, Pages 426-436

  Harder, P ^a   Grunze, M ^a   Dahint, R ^a   Whitesides, G M ^b   Laibinis, P E ^c  

^a UNIVERSITY OF HEIDELBERG   (Germany)

^b HARVARD UNIVERSITY   (United States)

^c USA   (United States)

Author keywords

[No Author keywords available]

Indexed keywords

ADSORPTION; CONFORMATIONS; FOURIER TRANSFORM INFRARED SPECTROSCOPY; GOLD; MOLECULES; MONOLAYERS; OLIGOMERS; PROTEINS; SILVER; X RAY PHOTOELECTRON SPECTROSCOPY;

ADSORPTION RESISTANCE; MOLECULAR CONFORMATION; OLIGOETHYLENE GLYCOL; PROTEIN ADSORPTION; SELF ASSEMBLED MONOLAYERS;

SURFACES;

EID: 0032495430     PISSN: 15206106     EISSN: None     Source Type: Journal    
DOI: 10.1021/jp972635z     Document Type: Article

References (63)

1. Harris, J. M., Ed. Poly(ethyleneglycol) chemistry: biotechnical and biomedical applications; Plenum Press: New York, 1992.
2. Bailey, F. E., Jr.; Koleske, J. Y. Poly(Ethylene Oxide); Academic Press: New York, 1976.
3. PEGs are also sometimes referred to as poly(ethylene oxide) (PEO) and poly(oxyethylene) (POE). In this paper, the term poly(ethylene glycol) will be used for polymers of all molecular weights.
4. Lee, J. H.; Kopecek, J.; Andrade, J. D. J. Biomed. Mater. Res. 1989, 23 (3), 351-368.
5. de Gennes, P. G. Ann. Chim. 1987, 77, 389. Taunton, H. J.; Toprakcioglu, C.; Fetters, L. J.; Klein, J. Nature 1988, 332, 712-714.
6. de Gennes, P. G. Ann. Chim. 1987, 77, 389. Taunton, H. J.; Toprakcioglu, C.; Fetters, L. J.; Klein, J. Nature 1988, 332, 712-714.
7. Jeon, S. I.; Lee, J. H.; Andrade, J. D.; de Gennes, P. G. J. Colloid Interface Sci. 1991, 142, 149-158.
8. Jeon, S. I.; Andrade, J. D. Ibid. 1991, 142, 159-166.
9. Gölander, C. G.; Herron, J. N.; Lim, K.; Claesson, P.; Stenius, P.; Andrade, J. D. In Poly(ethyleneglykol) chemistry: biotechnical and biomedical applications; Harris, J. M., Ed.; Plenum Press: New York, 1992; pp 221-245.
10. Lüsse, S.; Arnold, K. Macromolecules 1996, 29, 4251-4257.
11. Prime, K. L.; Whitesides, G. M. J. Am. Chem. Soc. 1993, 115, 10714-10721.
12. Wang, R. L. C.; Kreuzer, H. J.; Grunze, M. J. Phys. Chem. 1997, 101, 9767-9773.
13. Bain, C. D.; Troughton, E. B.; Tao, Y.-T.; Evall, J.; Whitesides, G. M.; Nuzzo, R. G. J. Am. Chem. Soc. 1989, 111, 321-335.
14. Pale-Grosdemange, C.; Simon, E. S., Prime, K. L.; Whitesides G. M. J. Am. Chem. Soc. 1991, 113, 12-20.
15. Bird, R.; Mrksich, M.; Whitesides, G. M. Manuscript in preparation.
16. Laibinis, P. E.; Whitesides, G. M.; Allara, D. L.; Tao, Y.-T.; Parikh, A. N.; Nuzzo, R. G. J. Am. Chem. Soc. 1991, 113, 7152-7167.
17. Long-chain alkanethiols have low solubilities in hexane. Oligo-(ethylene glycol)-terminated alkanethiols are less soluble in hexane and showed a better ordering when prepared from ethanol as compared to hexane solution.
18. We observed that oligo(ethylene glycol)-terminated SAMs after removal from the solution decompose in the dark in air at 45°C within a week. XP spectra showed a loss of ethylene glycol units and an oxidation of the thiol headgroup. At 20°C, first signs of degradation were visible after storage in air longer than about 1 month. Storage of the samples in daylight did not enhance the decomposition rate.
19. Ulman, A. An introduction to ultrathin organic films; Academic Press: London, 1991.
20. Allara, D. L.; Swalen, J. D. J. Phys. Chem. 1982, 86, 2700-2704.
21. Takahashi, Y.; Tadokoro, H. Macromolecules 1973, 6, 672-675.
22. Matsuura, H; Miyazawa, T. J. Polym. Sci., Part A-2 1969, 7, 1735-1744.
23. Liedberg, B.; Ivarsson, B.; Lundström, I. J. Biochem. Biophys. Meth. 1984, 9, 233-243.
24. Stenberg, E.; Persson, B.; Roos, H.; Urbaniczky, C. J. Colloid Interface Sci. 1991, 143, 513-526.
25. Engquist, I.; Lundström, I.; Liedberg, B. J. Phys. Chem. 1995, 99, 12257-12267.
26. Laibinis, P. E.; Bain, C. D.; Nuzzo, R. G.; Whitesides, G. M. J. Phys. Chem. 1995, 99, 7663-7676.
27. Dubois, L. H.; Zegarski, B. R.; Nuzzo, R. G. J. Am. Chem. Soc. 1990, 112, 570-579.
28. Snyder, R. G.; Strauss, H. L.; Elliger, C. A. J. Phys. Chem. 1982, 86, 5145-5150.
29. Koenig, J. L.; Angood, A. C. J. Polym. Sci., Part A-2 1970, 8, 1787-1796.
30. Both molten and amorphous are used to characterize the state of poly(ethylene glycol) at temperatures exceeding 350 K, because the spectra are considerably different from that of the crystalline polymer at lower temperatures (refs 2, 28). The helical splitting in the Raman spectra observed in the crystalline state disappears, and frequency shifts are observed. These changes indicate a loss of order and an appearance of added rotational isomers of trans, trans, trans conformations.
31. Matsuura, H.; Fukuhara, K. J. Polym. Sci., Part B 1986, 24, 1383-1400.
32. Bellamy, L. J. The Infrared Spectra of Complex Molecules; Chapman & Hall: London, 1980.
33. Minimum immersion times for the formation of complete, protein resistant EG6-OH monolayers varied from 15 s to 10 min. Similar differences by several orders of magnitude in adsorption kinetics have been observed for unfunctionalized alkanethiolates. See for example: Pan, W.; Durning, C. J.; Turro, N. J. Langmuir 1996, 12, 4469-4473, and references cited therein.
34. Nuzzo, R. G.; Dubois, L. H.; Allara, D. L. J. Am. Chem. Soc. 1990, 112, 558-564.
35. Nuzzo, R. G.; Fusco, F. A.; Allara, D. L. J. Am. Chem. Soc. 1987, 109, 2358-2367.
36. The deconvolution routine was started with the CH-stretching mode peak frequencies of the eight most dominant bands of polycrystalline alkanethiols as an initial guess. The line shape of the peaks was fixed as 50% Gaussian and 50% Lorentzian, and their half-widths and exact frequencies in the alkanethiolate spectrum were determined with a least-squares fitting routine.
37. Miyazawa, T.; Fukushima, K.; Ideguchi, Y. J. Chem. Phys. 1962, 37, 2764-2776.
38. -1. See for example: Dissanayake, M. A. K. L.; Frech, R. Macromolecules 1995, 28, 5312-5319.
39. -1 (ref 36).
40. Laibinis, P. E.; Whitesides, G. M. J. Am. Chem. Soc. 1992, 114, 1990-1995.
41. 22, because the reproducibility of formation of monolayers was much better for the longer chain lengths (ref 15).
42. Attenuation length means the thickness of material required to reduce the flux of the emitted photoelectrons by 1/e and is denoted by λ. λ is not identical with the inelastic mean free path except in the absence of elastic scattering.
43. According to the empirical approximation that the energy dependence of the mean free path scales with the kinetic energy and that the energy exponent is in the range 0.7-0.8 for organic materials (Tanuma, S.; Powell, C. J. Penn, D. R. Surf. Interface Anal. 1993, 20, 77-89), the IMFP (determined with a Mg Ka source) for the Ag 3d photoelectrons should be ∼0.5 Å lower than for the Au 4d photoelectrons.
44. Tanuma, S.; Powell, C. J.; Penn, D. R. Surf. Interface Anal. 1993, 21, 165-176.
45. Hansen, H. S.; Tougaard, S.; Biebuyck, H. J. Electron Spectrosc. Relat. Phenom. 1990, 58, 141-158.
46. Tanuma, S.; Powell, C. J.; Penn, D. R. Surf. Interface Anal. 1993, 21, 165-176.
47. Laibinis, P. E.; Bain, C. D.; Whitesides, G. M. J. Phys. Chem. 1991, 95, 7017-7021.
48. Jablonski, A.; Tilinin, I. S.; Powell, C. J. Phys. Rev. B 1996, 54, 10927-10937.
49. Tanuma et al. analyzed the IMFP for various organic compounds and found that the IMFP can be predicted from the number of valence electrons per molecular unit, molecular weight, density, and bandgap energy for nonconducters. The number of valence electrons is the same for a propylene unit or an ethylene glycol unit. The other parameters (density, atomic weight) are similar or have only little influence on the IMFP. We therefore expect that the IMFP for the oligo(ethylene glycol)s should be the same within experimental error than for unfunctionalized alkanethiolates. Tanuma, S.; Powell, C. J.; Penn, D. R. Surf. Interface Anal. 1993, 21, 165-176.
50. 2, the relative difference between model and experiment might be somewhat smaller, because the theoretical values assume a homogeneous film density and do not include defects and domain boundaries.
51. Fenter, P.; Eisenberger, P.; Li, J.; Camillone, N., III; Bernasek, S.; Scoles, G.; Ramanarayanan, T. A.; Liang, K. S. Langmuir 1991, 7, 2013-2016.
52. n = 13 for EG6-OH; n = 8 for EG3-OMe.
53. Horbett, T. A. Adsorption to Biomaterials from Protein Mixtures. In Proteins at Interfaces: Physicochemical and Biochemical Studies; Brash, J. L., Horbett, T. A., Eds.; ACS Symposium Series 343; American Chemical Society: Washington, DC, 1987; pp 239-260, and references cited therein.
54. Corno, C.; Ghelli, S.; Perego, G.; Platone, E. Colloid Polym. Sci. 1991, 269, 1133-1139.
55. Dubois, L. H.; Zegarski, B. R.; Nuzzo, R. G. J. Chem. Phys. 1993, 98, 678-688.
56. Fenter, P.; Eisenberger, P.; Liang, K. S. Phys. Rev. Lett. 1993, 70, 2447-2450.
57. Dhirani, A.; Hines, M. A.; Fisher, A. J.; Ismail, O.; Guyot-Sionnes, P. Langmuir 1995, 11, 2609-2614.
58. Ulman, A. Chem. Rev. 1996, 96, 1533-1554.
59. Matsuura, H.; Fukuhara, K. J. Mol. Struct. 1985, 126, 251-260.
60. Lopez, G. P.; Biebuyck, H. A.; Härter, R.; Kumar, A.; Whitesides, G. M. J. Am. Chem. Soc. 1993, 115, 10774-10781.
61. Szleifer, I. Curr. Opin. Solid State Mater. Sci. 1997, 2, 337-344.
62. Szleifer, I. Biophys. J. 1997, 72, 595-612.
63. See ref 11.