Abstract
In the last few years we have studied the dielectric properties of nearly dry biological materials as a function of their water content. Details of the experimental apparatus have been given1. Let us only mention here that our technique combines a digital balance to monitor sample’s weight with an a. c. bridge to record radiofrequency dielectric properties of a composite capacitor, designed to avoid metal contacts and to ensure uniform evaporation from the sample. The investigation of lysozyme powders was quite fruitful because we were able to assess the onset of a protonic percolative conductivity at a critical hydration threshold. This threshold was found to be coincident with the critical hydration for the onset of enzymatic activity3–7. This study was extended to other more complex biomaterials, of different origin: purple membrane8, artemia cysts9, and maize-seed components10. In all these cases a critical hydration for the onset of a biological function was already known, and our data showed the percolative threshold for proton motion to be correlated with the emergence of biological function11.
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References
G. Careri and A. Giansanti, Dielectric properties of nearly dry biological systems at megahertz frequencies, in: Membranes, Metabolism, and Dry Organisms A. C. Leopold, ed., Cornell University Press, Ithaca (1986).
J. A. Rupley, E. Gratton and G. Careri, Water and globular proteins, Trends Biochem. Sci. 8: 18 (1983).
J. A. Rupley and G. Careri, Protein hydration and function, Adv. Protein Chem. in press (1990).
J. A. Rupley, P. H. Yang and G. Tollin, Thermodynamic and related studies of water interacting with proteins, in: Water in polimers, ACS Symposium Series vol. 127 S. P. Rowlands, ed., American Chemical Society, Washington (1980).
G. Careri, M. Geraci, A. Giansanti and J. A. Rupley, Protonic conductivity of hydrated lysozyme powders at megahertz frequencies, Proc. Natl. Acad. Sci. U.S.A. 82: 5342 (1985).
G. Careri, A. Giansanti and J. A. Rupley, Proton percolation on hydrated lysozyme powders, Proc. Natl. Acad. Sci. U.S.A. 83: 6810 (1986).
G. Careri, A. Giansanti and J. A. Rupley, Critical exponents of protonic percolation in hydrated lysozyme powders, Phys. Rev. A37: 2703 (1988).
J. A. Rupley, L. Siemankowski, G. Careri and F. Bruni, Two dimensional protonic percolation on lightly hydrated purple membrane, Proc. Natl. Acad. Sci. U.S.A. 85: 9022 (1988).
F. Bruni, G. Careri and J. S. Clegg, Dielectric Properties of artemia cysts at low water contents, Biophys. J. 55: 331 (1989).
F. Bruni, G. Careri and A. C. Leopold, Critical exponents of protonic percolation in maize seeds, Phys. Rev. A40: 2803 (1989).
G. Careri, Emergence of function in disordered biomaterials, in: Symmetry in nature, a volume in honour of L. A. Radicati di Brozolo, Scuola Normale Superiore, Pisa (1989).
R. Zallen, The Physics of Amorphous Solids, Wiley, New York (1983).
D. Stauffer, Introduction to Percolation Theory, Taylor and Francis, London (1985).
G. Careri, A. Giansanti and J. A. Rupley, Detection of protonic percolation on hydrated lysozyme powders, in: Disordered Solids: structures and processes, B. Di Bartolo ed., Plenum Press, New York (1989).
P. Pissis and A. Anagnostopoulou Konsta, Protonic percolation on hydrated lysozyme powders studied by the method of thermally stimulated depolarisation currents method, J. Phys. D: Appl. Phys. 23: 932 (1990).
R. F. Voss, R. B. Laibowitz and E. I. Allessandrini, Fractal (scaling) clusters in thin gold films near the percolation threshold, Phys. Rev. Lett. 49: 1441 (1982).
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Careri, G., Giansanti, A. (1991). Protonic Conductivity in Biomaterials in the Frame of Percolation Model. In: Peliti, L. (eds) Biologically Inspired Physics. NATO ASI Series, vol 263. Springer, Boston, MA. https://doi.org/10.1007/978-1-4757-9483-0_22
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DOI: https://doi.org/10.1007/978-1-4757-9483-0_22
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