AWeak Current Amperometric Technique in Physiological and Bioelectromagnetic Measurements: A Weak Current Amperometric Technique

Masroor Hussain Shah Bukhari; John H. Miller Jr.; Zahoor Hussain Shah

Authors

Masroor Hussain Shah Bukhari Unit of Experimental Physiology and Biophysics, Department of Physiology, Dow University of Health Sciences, Karachi-74200, Pakistan
John H. Miller Jr. Department of Physics, University of Houston, Houston, Texas 77204, USA
Zahoor Hussain Shah Department of Chemistry, Faculty of Marine Sciences, Lasbela University, Uthal, Lasbela 90150, Balochistan, Pakistan

Keywords:

intrinsic currents, biosensors, bio-amperometry, bioelectromagnetic measurement

Abstract

A technique for measuring ultra-low electric currents from living cells, using electrodes, biosensors or magnetic detectors is reported, based on the design of a sensitive, ultra-low-noise trans-impedance amplifier. This technique offers a low-noise, low current measurement capability down on the order of 2 x 10-14 amperes, with specifications such as input leakage current of less than 1 x 10-15 amperes and a dynamic range of 30-100 x 10-14 amperes. Maximum bandwidth of roughly 10KHz was observed, while working in the specified dynamic range. This set of specifications is quite satisfactory and desirable for many low-frequency applications in bioelectromagnetism and bio-amperometry. The technique finds numerous applications in studying intrinsic cellular fields and induced currents originated in cells under physiological conditions. A few applications envisaged for its possible utility include bio-sensing amperometry, general studies in bioelectromagnetism and ion transport studies in plasma membrane and mitochondrial inner membrane, by incorporation of the amplifier with suitable micro-electrodes or nano-scale electrical, magnetic or optical sensors.

AWeak Current Amperometric Technique in Physiological and Bioelectromagnetic Measurements