<abstract xmlns="http://www.w3.org/1999/xhtml"><p>In this study, three-electrode based electric cell-substrate impedance sensing (ECIS) devices were used to study the electrical properties of blood and its constituents using electrochemical impedance spectroscopy. The three-electrode based ECIS devices were fabricated by using micromachining technology with varying sizes for working, reference and counter electrodes. The blood and its constituents such as serum, plasma, and red blood cells (RBCs) were prepared by conventional methods and stored for impedance measurement using fabricated microdevices. Equivalent circuits for blood, serum, plasma and RBCs were proposed using the software package ZSimpWin to validate the experimental data. The proposed equivalent circuit models of blood and its components have excellent agreement up to a frequency of 1 MHz. It is evident from the experimental results that blood and its components have specific impedance signatures that decrease with the increase of frequency. Blood shows higher impedance than the other samples in the lower frequency range (&lt;50 kHz). It was also found that above 50 kHz, the impedance value of RBCs is nearly the same as whole blood. The impedance of serum and plasma steadily decreases with the increase of frequency up to 100 kHz and flattens out after that. The minimum impedance value achieved for serum and plasma is much less than the value obtained for whole blood.</p></abstract>

In this study, three-electrode based electric cell-substrate impedance sensing (ECIS) devices were used to study the electrical properties of blood and its constituents using electrochemical impedance spectroscopy. The three-electrode based ECIS devices were fabricated by using micromachining technology with varying sizes for working, reference and counter electrodes. The blood and its constituents such as serum, plasma, and red blood cells (RBCs) were prepared by conventional methods and stored for impedance measurement using fabricated microdevices. Equivalent circuits for blood, serum, plasma and RBCs were proposed using the software package ZSimpWin to validate the experimental data. The proposed equivalent circuit models of blood and its components have excellent agreement up to a frequency of 1 MHz. It is evident from the experimental results that blood and its components have specific impedance signatures that decrease with the increase of frequency. Blood shows higher impedance than the other samples in the lower frequency range (<50 kHz). It was also found that above 50 kHz, the impedance value of RBCs is nearly the same as whole blood. The impedance of serum and plasma steadily decreases with the increase of frequency up to 100 kHz and flattens out after that. The minimum impedance value achieved for serum and plasma is much less than the value obtained for whole blood.

Impedimetric characterization of human blood using three-electrode based ECIS devices

Journal of Electrical Bioimpedance

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.

In this study, three-electrode based electric cell-substrate impedance sensing (ECIS) devices were used to study the electrical properties of blood and its...

Devices	Electrode dimensions (μm²)	Distance between electrodes ( μm)
Design 1	WE- 50×50, RE- 500×500, CE- 500×500	100
Design 2	WE- 100×100, RE-1000×1000, CE- 1000×1000	100
Design 3	WE- 150×150, RE-1500×1500, CE- 1500×1500	100
Design 4	WE- 200×200, RE-2000×2000, CE- 2000×2000	100

ECs	Design 1		Design 2		Design 3		Design 4
	Data	e %	Data	e %	Data	e %	Data	e %
R_S (Ω)	991	5.76	774	4.24	604	5.81	445	5.9
C_S (Fs^n-1) ×10^-9	20.2	6.56	30.32	5.2	33.1	6.56	49.5	6.94
R_I (Ω)	2225	2.98	1651	2.4	1371	2.98	998	3.21
Q_M (Fs^n-1) ×10^-3	1289	9.29	1583	7.8	2046	9.3	2681	10.6
n	0.80	0.59	0.61±	0.45	0.60	0.41	0.61	0.46
value χ²	3.7×10^-3		2.62×10^-3		3.8×10^-3		4.79×10^-3

ECs	Design 1		Design 2		Design 3		Design 4
	Data	e %	Data	e %	Data	e %	Data	e %
Plasma
R_S (Ω)	761	0.8	555	0.8	395	0.78	294	0.75
C_S(Fs^n-1) ×10^-9	8	2.23	11	2.13	15	2.07	20	2
n	0.91	0.02	0.91	0.02	0.91	0.02	0.91	0.02
R_CT (kΩ)	1224	6.5	874	6.1	616	5.8	462	5.6
χ2 value	8.45×10^-4		7.74×10^-4		7.28×10^-4		6.79×10^-4
Serum
R_S (Ω)	833	0.73	596	0.68	395	0.65	280	0.62
C_S(Fs^n-1)×10^-9	7.33	1.88	9.90	1.77	14.8	1.7	20.6	1.61
n	0.90	0.02	0.90	0.02	0.90	0.02	0.90	0.02
R_CT (kΩ)	882	3.46	626	3.22	415	3.08	292	2.90
χ2 value	5.97×10^-4		5.28×10^-4		4.83×10^-4		4.36×10^-4

ECs	Design 1		Design 2		Design 3		Design 4
	Data	e %	Data	e %	Data	e %	Data	e %
R_S (Ω)	1353	1.83	1112	1.85	906.5	1.79	654.8	1.74
C_S (Fs^n-1) ×10^-9	46.12	4.98	55.13	5.01	66.43	4.81	90.19	4.64
(RΩ_I)	1588	3.01	1306	2.99	1060	2.81	767	2.67
Q_M (Fs^n-1) ×10^-9	5.05	3.16	6.14	3.16	7.52	3	10.36	2.87
n	0.92	0.03	0.92	0.03	0.92	0.03	0.92	0.03
χ² value	1.06×10^-3		1.06×10^-3		9.66×10^-4		8.96×10^-4

Impedimetric characterization of human blood using three-electrode based ECIS devices

Article Category: Articles

Published Online: Jul 28, 2012

Page range: 12 - 19

Received: Jan 16, 2012

DOI: https://doi.org/10.5617/jeb.238

Keywords
Bioimpedance, blood, serum and plasma, red blood cells, equivalent circuit

© 2012 Rangadhar Pradhan, Analava Mitra, Soumen Das, published by Sciendo

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.

Fig. 1

Fig. 2

Fig. 3

Fig. 4

Fig.5

Fig. 6

Fig. 7

Dimensions of different design of three electrode devices.

Values of electric components of RBC for different designs with relative standard error (e %).

Values of electric components of plasma and serum for different designs with relative standard error (e %).

Values of electric components of blood for different designs with relative standard error (e %)

Impedimetric characterization of human blood using three-electrode based ECIS devices

Article Category: Articles

Published Online: Jul 28, 2012

Page range: 12 - 19

Received: Jan 16, 2012

DOI: https://doi.org/10.5617/jeb.238

KeywordsBioimpedance, blood, serum and plasma, red blood cells, equivalent circuit

© 2012 Rangadhar Pradhan, Analava Mitra, Soumen Das, published by Sciendo

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.

Fig. 1

Fig. 2

Fig. 3

Fig. 4

Fig.5

Fig. 6

Fig. 7

Dimensions of different design of three electrode devices.

Values of electric components of RBC for different designs with relative standard error (e %).

Values of electric components of plasma and serum for different designs with relative standard error (e %).

Values of electric components of blood for different designs with relative standard error (e %)

Keywords
Bioimpedance, blood, serum and plasma, red blood cells, equivalent circuit