Towards the application of fast Fourier transform - scanning electrochemical impedance microscopy (FFT-SEIM)

In this research we are proposing a combination of scanning electrochemical microscopy (SECM) and fast Fourier transform-electrochemical impedance spectroscopy (FFT-EIS) as a new tool, which we entitled 'fast Fourier transform - scanning electrochemical impedance microscopy (FFT-SEIM)' suitable for the evaluation and treatment of highly complicated electrochemical systems, in which the electrical signal is under limitations of very small surface area of the electrode and Faradaic process is controlled by slow diffusion of species in the solution. The identification and in situ treatment of unhealthy tissues at cellular level is futuristic direction of the biomedical research, which requires completely newtools and advanced techniques. In this manuscript we show that the combination of SECM and FFT-EIS systems can operate well in the absence of the additional redox probes, which are harmful for living cells and tissues. We are also addressing how some challenging electrochemical problems, which are arising during the application of FFT-SEIM in the absence of redox probe, can be solved. Particularly, in this research we have demonstrated how the quality of FFT-SEIM signal can be increased by the adjustment of FFT-SEIM parameters. Particularly, the reduction of preconditioning duration before the start of the FFT-EIS measurement and very short duration of FFT-EIS measurement, which takes just a little bit longer time than that required to register single period of sin-wave at lowest frequency of registered EIS spectra, significantly increased the quality of gathered EIS spectra. (C) 2020 Elsevier B.V. All rights reserved.