Abstract:

Using sodium alginate-starch gel as a fixing agent, small intestine tissues of Sprague-Dawley rats were fixed
between two nuclear micro porous membranes, forming a sandwich-type membrane, and then fixed to a glassy carbon
electrode to make a biosensor electrode. By using electrochemical workstation for the detection of the response current
from receptor stimulation by different resveratrol concentrations, the results showed that the lowest limit of detection
of this biosensor for resveratrol was 1 × 10-13 mol/L and the highest rate of change in response current was found at the
concentration of 8.5 × 10-12 mol/L, indicating that the resveratrol receptor was saturated at this point. The role of resveratrol
and its receptor was fitted to a hyperbolic curve with Origin software (R2 = 0.988 7). It showed that the correlation is high.
The binding constant and dissociation constant of resveratrol and its receptor evaluated by the double-reciprocal plot method
were 1.207 × 10-11 and 1.118 × 10-12, respectively. Thus the number of receptors to every cell is estimated to be about 85.
By comparing response values of resveratrol biosensor immobilized on rat intestinal epithelial tissue to the interaction of
resveratrol with the bare electrode, the response value of the small intestine tissue to resveratrol clearly gained amplified
function of intracellular signaling system with a magnification rate of up to 100. Meanwhile, the cell receptors obviously
rendered the biosensor saturabile and the typical characteristic was similar to the enzymatic reaction kinetic equation. This
study for the first time accomplished the quantitative determination of the interactions between resveratrol and receptors
and the dynamic law of signal transmission in the body through biosensors. This will provide new methods for resveratrol
receptor analysis, separation and purification, signal transmission and biological function evaluation.

Key words: biosensor, resveratrol, immobilization, small intestine