Engineering Self‐Powered Electrochemical Sensors Using Analyzed Liquid Sample as the Sole Energy Source

Abstract

Many healthcare and environmental monitoring devices use electrochemical techniques to detect and quantify analytes. With sensors progressively becoming smaller—particularly in point‐of‐care (POC) devices and wearable platforms—it creates the opportunity to operate them using less energy than their predecessors. In fact, they may require so little power that can be extracted from the analyzed fluids themselves, for example, blood or sweat in case of physiological sensors and sources like river water in the case of environmental monitoring. Self‐powered electrochemical sensors (SPES) can generate a response by utilizing the available chemical species in the analyzed liquid sample. Though SPESs generate relatively low power, capable devices can be engineered by combining suitable reactions, miniaturized cell designs, and effective sensing approaches for deciphering analyte information. This review details various such sensing and engineering approaches adopted in different categories of SPES systems that solely use the power available in liquid sample for their operation. Specifically, the categories discussed in this review cover enzyme‐based systems, battery‐based systems, and ion‐selective electrode‐based systems. The review details the benefits and drawbacks with these approaches, as well as prospects of and challenges to accomplishing them.

Hydrovoltaic Nanogenerators for Self‐Powered Sweat Electrolyte Analysis

“…[ 14 ] The frequent recharge requirement may also constrain the usability of the sensor for real‐time monitoring, while also adding to the maintenance cost for users. [ 15 ]…”

“…[14] The frequent recharge requirement may also constrain the usability of the sensor for real-time monitoring, while also adding to the maintenance cost for users. [15] In recent years, self-powered sensing systems have attracted much attention and found applications as wearable sensors for health diagnostics. [16] The self-powered sensors are capable of harvesting environmental energy or matter to generate electrical signals.…”

Advanced Self-Powered Biofuel Cells with Capacitor and Nanogenerator for Biomarker Sensing

“…A printed microstructure holds the mechanical and electrical properties under extreme strain to sustain higher mechanical deformation. − A skin-attached EBFC creates an ionic current over the skin’s surface by enzymatic electrochemical processes. , Sweat electrolyte-based BFCs and supercapacitors offer high energy density/power density to result in energy-independent sensing for continuous run . SPBs require intermittent powering with a capacitor for continuous charging and discharging by using interfaced electronic circuit. , EBFCs with a two-electrode system separate anodic and cathodic counterparts through chemical energy conversion from body fluid into electrical energy. Internal modification of anode requires coencapsulation of enzyme and cofactor (glucose dehydrogenase (GOD) and nicotinamide adenine dinucleotide (NAD + )) in a framework as microreactors with lower surface energy.…”

Self-Powered Potentiometric Sensor Based on a Passive Signal Amplifier with Electronic Paper Display

“…They have progressed rapidly over the past decades. However, an external power supply, usually a battery, is always needed . This battery hinders progress in the further miniaturization of portable sensors .…”

“…However, an external power supply, usually a battery, is always needed. 1 This battery hinders progress in the further miniaturization of portable sensors. 2 Self-powered electrochemical sensors (SPESs) omit external power sources and rely only on harvested energy for their operation.…”