F. Lacy et al., DISTINGUISHING BETWEEN ACTIVATED AND NONACTIVATED EOSINOPHILS BY AC-IMPEDANCE MEASUREMENTS, IEEE transactions on biomedical engineering, 43(2), 1996, pp. 218-221
A cellular electrical impedance device which can detect the activated
state of eosinophils has been developed and tested. This impedance dev
ice consists of a small gold electrode (50 mu m x 50 mu m) and a large
gold electrode (1.5 cm x 0.5 cm) on a glass substrate, and it was fab
ricated by standard photolithographic techniques. Eosinophils, which b
elong to the granulocytic class of white blood cells, exhibit differen
t physical properties when they change from the nonactivated state to
the activated state. Hypothetically, these changes should correspond t
o a change in the measured electrical impedance. In this paper, data f
rom the measured electrical impedance of eosinophils is presented. The
measurements show that the average impedance of the activated eosinop
hils is 26% lower than the average impedance of the nonactivated eosin
ophils. Statistical analysis of the measured data shows that there is
a significant difference between the measured impedances of activated
and nonactivated eosinophils.