Fast Sub-Hz potentiostatic/galvanostatic bio-impedance measurements using chaotic oscillators

Area of Science:

• Electrical Engineering
• Biomedical Engineering
• Signal Processing

Background:

• Traditional bio-impedance spectroscopy (BIS) at ultra-low frequencies (sub-Hz) is time-consuming using frequency-sweep methods.
• Existing narrow-band periodic excitation signals also present temporal limitations for comprehensive spectral analysis.

Purpose of the Study:

• To develop and validate a novel impedance measurement technique utilizing wide-band chaotic signals for faster sub-Hz bio-impedance spectroscopy.
• To assess the performance of this technique in both potentiostatic and galvanostatic modes.

Main Methods:

• Implementation of a bio-impedance measurement technique employing wide-band chaotic signals across the [Formula: see text] frequency range.
• Experimental validation using commercial components and a custom-designed 65nm CMOS enhanced Howland current pump.
• Testing in both potentiostatic and galvanostatic operational modes.

Main Results:

• The proposed chaotic signal-based technique successfully measured bio-impedance spectra at ultra-low frequencies.
• Experimental validation demonstrated the technique's efficacy across the specified frequency range.
• Accuracy was confirmed by comparing measurements on fruit samples with a research-grade electro-chemical station.

Conclusions:

• Wide-band chaotic signals offer a significantly faster alternative for ultra-low frequency bio-impedance spectroscopy.
• The developed technique is accurate and versatile, applicable in both potentiostatic and galvanostatic configurations.
• This advancement has potential implications for improving the efficiency of bio-impedance analysis in various applications.