Bìol. Tvarin, 2014, volume 16, issue 1, pp. 42–48


V. V. Havrylyak1, O. S. Iaremkevych2, H. M. Sedilo3

havvita@ukr.net, This email address is being protected from spambots. You need JavaScript enabled to view it.

1Institute of Animal Biology NAAS,
38 Stus str., Lviv 79034, Ukraine
2Lviv National Polytechnic University,
3/4 St. Yura sq., Lviv 79013, Ukraine
3Institute of Agriculture of Carpathian region NAAS,
5 Hrushevskoho str., Obroshyno village, Lviv region, 81115, Ukraine

The paper presents the results of the study of the biophysical characteristics of wool fibers by impedance spectroscopy under the action of the alternating current at the frequency from 1 to 100 kHz. In the experiment wool fibers with an average diameter of d=28.4 μm were used and its treatment with 10 % aqueous solution of thioglicolic acid at 37 ° C for 15 min was designed.

Structural changes in the surface of the native wool fibers surface and under the influence of thioglicolic acid were evaluated by scanning electron microscopy. Effect of thioglicolic acid on wool fiber was accompanied by destruction of its cuticle layer.

It has been shown that the electric impedance of the native wool fiber at frequency current from 1 to 40 kHz is significantly higher compared to chemically treated wool. The lowest value of impedance was fixed at the frequency of 10 kHz (5.36 Ohm and 3.03 Ohm, respectively for the native and chemically processed fibers). At the frequency of 40 kHz impedance of native wool fiber increased by 58% (P≤0,05) and chemically treated wool fibers was 2.6 times higher (P≤0,001) compared to impedance measured at the frequency of 10 kHz. Bioimpedance differences of native and processed wool fibers associated with changes of proteins structure by reducing of disulfide and salt bonds between of keratin molecules after the penetration of the aqueous solution of thioglicolic acid into the fiber. It has been detected that the phase angle j of permittivity of chemically treated wool fibers, regardless of the frequency of alternating current, is lower compared to the native wool fibers.


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