Design and Development of a Low‑Cost Arduino‑Based Electrical BioImpedance Spectrometer

Background: Bioimpedance spectroscopy (BIS) is a device used to measure electrical impedance at frequencies from ۰ Hz to ۱ MHz. Many clinical diagnosis and fundamental researches, especially in the field of physiology and pathology, rely on this device. The device can be used to estimate human body composition, through the information of total body water, extracellular fluid and intracellular fluid, fat-free mass, and fat mass from its impedance. BIS analysis can provide physiological statuses such as ischemia, pulmonary edema, skin cancer, and intramuscular tumors. BIS is expected to be used even more widely, both for hospital or home-based use, particularly because BIS handy, compact, inexpensive, and less power-consuming with adequately accurate real-time. In previous research, the BIS design was based on the magnitude-ratio and phase-difference detection using the AD۸۳۰۲ gain-phase detector method which resulted in an operating range between ۲۰ kHz and ۱ MHz. However, the impedance was obtained from the logarithmic ratio magnitude which caused the device to have limited accuracy at frequencies <۲۰ kHz. Methods: In this research, we conduct design and development of a low-cost arduino-based electrical bioimpedance spectrometer. Results: The low-cost bioimpedance spectrometry was successfully developed using AD۹۸۵۰ as the programmable function generator, OPA۲۱۳۴ as the OpAm of voltage-controlled current source, AD۶۲۰A as the instrument amplifier and AD۵۳۶A as the alternating current to direct current converter which could work accurately from ۰ Hz to ۱۰۰ kHz. Conclusion: The multi-frequency bioimpedance device developed in this research has the capability to safely measure the impedance of the human body due to its relatively stable electric current, which is equal to (۰.۳۷۰ ± ۰.۰۰۳) mA with frequencies ranging from ۵ to ۲۰۰ kHz and has an accuracy of over ۹۰% in the frequency range of ۱۰ Hz to ۱۰۰ kHz.

Keywords:

Arduino based , electrical bioimpedance , low‑cost , spectrometer