POISED-5, a portable on-board electrochemical impedance spectroscopy biomarker analysis device

Abstract

Point-of-care medical devices offer the potential for rapid biomarker detection and reporting of medical conditions, thereby bypassing the requirements for offline clinical laboratory facilities in many cases. Label-free electrochemical techniques are suitable for use in handheld diagnostic devices due the inherent electronic detection modality and low requirement for processing reagents. While electrochemical impedance sensing is widely used in tissue analysis such as body composition measurement, its use in point-of-care patient testing is yet to be widely adopted. Here we have considered a number of issues currently limiting the translation of electrochemical impedance sensing into clinical biosensor devices. Specifically, we have addressed the current requirement for these sensors to be connected to an external processor by applying a minimum number of frequencies required for optimized biomarker detection, and subsequently delivering analytics within the measurement device. The POISED-5 device was evaluated using a sensor for the ovarian cancer biomarker cancer antigen 125 (CA125), demonstrating performance comparable to standard laboratory equipment, with direct interpretation of response signal amplitude substituting traditional impedance component calculation and model fitting.

A Small yet Complete Framework for a Potentiostat, Galvanostat, and Electrochemical Impedance Spectrometer

“…To help students understand these interrelated and complex topics, electrochemical experiments in laboratory classes play a significant role since experiments can visualize the electrical effect(s) on a material of interest (e.g., Faradaic efficiency for the evolution of continuous bubbles of hydrogen gas from an electrode). On this basis, various groups have reported potentiostats, galvanostats, and/or electrochemical impedance spectrometers (EIS) as task-specific devices for their respective (educational) topics. − These structures of devices are generalized to a system consisting of three functionalities, a view, a controller, and core analog circuit(s), as depicted in Scheme , where the view represents a graphical user interface prepared by programming language(s), the analog circuit represents an electrical interface converting chemical response(s) from an electrochemical cell of interest to the form of electrical response(s), and the controller, which is typically a general-purpose microprocessor with peripheral task-specific integrated circuits, mediates between the view and analog circuit(s). The balance between functionality, capability, and cost of a device depends on how the three functionalities are purposefully configured.…”

“…The balance between functionality, capability, and cost of a device depends on how the three functionalities are purposefully configured. Accordingly, these reported devices are categorized into four classes: (1) wireless electrochemical detector as an IoT device; ,,,,,, (2) stand-alone device not requiring an external computer; ,,,,, (3) single-chip to miniaturize a device; ,,, and (4) electric-topologically multifunctional device as general-purpose equipment in a laboratory ,, (see the Supporting Information for the detailed classification of low-cost (<1000 USD) electrochemical devices reported previously). Among these categories, the multifunctional device can play a vital role for students investigating various dimensions of a subject of interest and understand the subject multidirectionally.…”

Establish pre-clinical diagnostic efficacy for parathyroid hormone as a point-of-surgery-testing-device (POST)

“…The physicochemical properties of the READ sensor platform captures specific target PTH interaction using electrochemical impedance spectroscopy (EIS) as the detection modality. EIS has been incorporated in many point-of-care sensor applications owing to its label-free approach with the least procedural complexity to acquire results 13 – 17 . A major advantage of using EIS technique is its ability to capture subtle electrochemical changes by optimizing input parameters.…”

Direct monitoring of breast and endometrial cancer cell epigenetic response to DNA methyltransferase and histone deacetylase inhibitors

“…Furthermore, they offer limits of detection of methylated DNA within the levels reported to be found circulating in plasma (Stewart and Tsui, 2018). In addition, instrumentation required to make such measurements is low-cost, with instrument refinement reducing costs even further (Sawhney and Conlan, 2019). Gold and carbon -based electrode systems remain the most utilized working electrode materials, despite many other materials having been evaluated (Krejcova et al, 2017), and have been used in screen printed formats that offer low cost per unit, and do not require extensive preparation to obtain a pristine surface prior to use.…”