메뉴 건너뛰기




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

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

Author keywords

[No Author keywords available]

Indexed keywords

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

EID: 0032495430     PISSN: 15206106     EISSN: None     Source Type: Journal    
DOI: 10.1021/jp972635z     Document Type: Article
Times cited : (1202)

References (63)
  • 3
    • 11644286223 scopus 로고    scopus 로고
    • note
    • 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.
  • 5
    • 0003627868 scopus 로고
    • de Gennes, P. G. Ann. Chim. 1987, 77, 389. Taunton, H. J.; Toprakcioglu, C.; Fetters, L. J.; Klein, J. Nature 1988, 332, 712-714.
    • (1987) Ann. Chim. , vol.77 , pp. 389
    • De Gennes, P.G.1
  • 17
    • 11644281802 scopus 로고    scopus 로고
    • note
    • 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
    • 11644295419 scopus 로고    scopus 로고
    • note
    • 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.
  • 30
    • 11644310823 scopus 로고    scopus 로고
    • note
    • 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.
  • 33
    • 0001455661 scopus 로고    scopus 로고
    • and references cited therein
    • 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.
    • (1996) Langmuir , vol.12 , pp. 4469-4473
    • Pan, W.1    Durning, C.J.2    Turro, N.J.3
  • 36
    • 11644293671 scopus 로고    scopus 로고
    • note
    • 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.
  • 39
    • 85088668612 scopus 로고    scopus 로고
    • note
    • -1 (ref 36).
  • 41
    • 85088668486 scopus 로고    scopus 로고
    • note
    • 22, because the reproducibility of formation of monolayers was much better for the longer chain lengths (ref 15).
  • 42
    • 11644272576 scopus 로고    scopus 로고
    • note
    • 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
    • 0027266185 scopus 로고
    • 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.
    • (1993) Surf. Interface Anal. , vol.20 , pp. 77-89
    • Tanuma, S.1    Powell, C.J.2    Penn, D.R.3
  • 49
    • 0028387002 scopus 로고
    • 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.
    • (1993) Surf. Interface Anal. , vol.21 , pp. 165-176
    • Tanuma, S.1    Powell, C.J.2    Penn, D.R.3
  • 50
    • 11644280596 scopus 로고    scopus 로고
    • note
    • 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.
  • 52
    • 11644299069 scopus 로고    scopus 로고
    • note
    • n = 13 for EG6-OH; n = 8 for EG3-OMe.
  • 53
    • 0002341358 scopus 로고
    • Adsorption to Biomaterials from Protein Mixtures
    • J. L., Horbett, T. A., Eds.; ACS Symposium Series 343; American Chemical Society: Washington, DC, and references cited therein
    • 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.
    • (1987) Proteins at Interfaces: Physicochemical and Biochemical Studies; Brash , pp. 239-260
    • Horbett, T.A.1
  • 58
    • 0345979435 scopus 로고    scopus 로고
    • Ulman, A. Chem. Rev. 1996, 96, 1533-1554.
    • (1996) Chem. Rev. , vol.96 , pp. 1533-1554
    • Ulman, A.1
  • 63
    • 11644297863 scopus 로고    scopus 로고
    • See ref 11
    • See ref 11.


* 이 정보는 Elsevier사의 SCOPUS DB에서 KISTI가 분석하여 추출한 것입니다.