Towards self-powered and autonomous wearable glucose sensor

Blood glucose diagnostic systems are a world-wide success story. Nevertheless, all the painless solutions available are too expensive to be disposable. We aim to bridge this gap by developing a painless disposable diabetes diagnostic patch. Our envisaged device is fully integrated and autonomous: harvests the required energy from the environment and features sensor autocalibration in real-time. In this paper, we present the design and preliminary results of the different parts in the wearable patch: electrochemical glucose sensor developed on scalable PCB technology, biofuel cell based on glucose in the biofluid sample, and instrumentation electronics designed on a PCB with energy and data management blocks

Wearable Skin-Worn Enzyme-Based Electrochemical Devices: Biosensing, Energy Harvesting, and Self-Powered Sensing

Integrating enzymes with wearable electrochemical systems delivers extraordinary functional devices, including biosensors and biofuel cells (BFCs). Strategies employing enzyme-based bioelectronics represent a unique foundation of wearables because of specific enzyme recognition and catalytic activities. Therefore, such electrochemical biodevices on various platforms, e.g., tattoos, textiles, and wearable accessories, are interesting. However, these devices need effective power sources, requiring combining effective energy sources, such as BFCs, onto compact and conformal platforms. Advantageously, bioenergy-harvesting BFCs can also act as self-powered sensors, simplifying wearable systems. Challenges pertaining to energy requirements and the integration of biocatalysts with electrodes should be considered. In this chapter, we detail updated advancement in skin-worn devices, including biosensors, BFCs, and self-powered sensors, along with engineering designs and on-skin iontophoretic strategies to extract biofluids. Crucial parameters including mechanical/material aspects (e.g., stretchability), electrochemistry, enzyme-related views (e.g., electron shuttles, immobilization, and behaviors), and oxygen dependency will be discussed, along with outlooks. Understanding such challenges and opportunities is important to revolutionize wearable devices for diverse applications

Wearable electrochemical biosensors in North America

Tremendous research and commercialization efforts around the world are focused on developing novel wearable electrochemical biosensors that can noninvasively and continuously screen for biochemical markers in body fluids for the prognosis, diagnosis and management of diseases, as well as the monitoring of fitness. Researchers in North America are leading the development of innovative wearable platforms that can comfortably comply to the human body and efficiently sample fluids such as sweat, interstitial fluids, tear and saliva for the electrochemical detection of biomarkers through various sensing approaches such as potentiometric ion selective electrodes and amperometric enzymatic sensors. We start this review with a historical timeline overviewing the major milestones in the development of wearable electrochemical sensors by North American institutions. We then describe how such research efforts have led to pioneering developments and are driving the advancement and commercialization of wearable electrochemical sensors: from minimally invasive continuous glucose monitors for chronic disease management to non-invasive sweat electrolyte sensors for dehydration monitoring in fitness applications. While many countries across the globe have contributed significantly to this rapidly emerging field, their contributions are beyond the scope of this review. Furthermore, we share our perspective on the promising future of wearable electrochemical sensors in applications spanning from remote and personalized healthcare to wellness

Triboelectric Effect Enabled Self-Powered, Point-of-Care Diagnostics: Opportunities for developing ASSURED and REASSURED devices

The use of rapid point-of-care (PoC) diagnostics in conjunction with physiological signal monitoring has seen tremendous progress in their availability and uptake, particularly in low- and middle-income countries (LMICs). However, to truly overcome infrastructural and resource constraints, there is an urgent need for self-powered devices which can enable on-demand and/or continuous monitoring of patients. The past decade has seen the rapid rise of triboelectric nanogenerators (TENGs) as the choice for high-efficiency energy harvesting for developing self-powered systems as well as for use as sensors. This review provides an overview of the current state of the art of such wearable sensors and end-to-end solutions for physiological and biomarker monitoring. We further discuss the current constraints and bottlenecks of these devices and systems and provide an outlook on the development of TENG-enabled PoC/monitoring devices that could eventually meet criteria formulated specifically for use in LMICs.Ulster Universityhttp://www.mdpi.com/journal/micromachineshj2021Electrical, Electronic and Computer Engineerin

Fully Integrated Biochip Platforms for Advanced Healthcare

Recent advances in microelectronics and biosensors are enabling developments of innovative biochips for advanced healthcare by providing fully integrated platforms for continuous monitoring of a large set of human disease biomarkers. Continuous monitoring of several human metabolites can be addressed by using fully integrated and minimally invasive devices located in the sub-cutis, typically in the peritoneal region. This extends the techniques of continuous monitoring of glucose currently being pursued with diabetic patients. However, several issues have to be considered in order to succeed in developing fully integrated and minimally invasive implantable devices. These innovative devices require a high-degree of integration, minimal invasive surgery, long-term biocompatibility, security and privacy in data transmission, high reliability, high reproducibility, high specificity, low detection limit and high sensitivity. Recent advances in the field have already proposed possible solutions for several of these issues. The aim of the present paper is to present a broad spectrum of recent results and to propose future directions of development in order to obtain fully implantable systems for the continuous monitoring of the human metabolism in advanced healthcare applications

Self-Powered Portable Electronic Reader for Point-of-Care Amperometric Measurements

In this work, we present a self-powered electronic reader (e-reader) for point-of-care diagnostics based on the use of a fuel cell (FC) which works as a power source and as a sensor. The self-powered e-reader extracts the energy from the FC to supply the electronic components concomitantly, while performing the detection of the fuel concentration. The designed electronics rely on straightforward standards for low power consumption, resulting in a robust and low power device without needing an external power source. Besides, the custom electronic instrumentation platform can process and display fuel concentration without requiring any type of laboratory equipment. In this study, we present the electronics system in detail and describe all modules that make up the system. Furthermore, we validate the device's operation with different emulated FCs and sensors presented in the literature. The e-reader can be adjusted to numerous current ranges up to 3 mA, with a 13 nA resolution and an uncertainty of 1.8%. Besides, it only consumes 900 µW in the low power mode of operation, and it can operate with a minimum voltage of 330 mV. This concept can be extended to a wide range of fields, from biomedical to environmental applications

A comprehensive survey of wireless body area networks on PHY, MAC, and network layers solutions

Recent advances in microelectronics and integrated circuits, system-on-chip design, wireless communication and intelligent low-power sensors have allowed the realization of a Wireless Body Area Network (WBAN). A WBAN is a collection of low-power, miniaturized, invasive/non-invasive lightweight wireless sensor nodes that monitor the human body functions and the surrounding environment. In addition, it supports a number of innovative and interesting applications such as ubiquitous healthcare, entertainment, interactive gaming, and military applications. In this paper, the fundamental mechanisms of WBAN including architecture and topology, wireless implant communication, low-power Medium Access Control (MAC) and routing protocols are reviewed. A comprehensive study of the proposed technologies for WBAN at Physical (PHY), MAC, and Network layers is presented and many useful solutions are discussed for each layer. Finally, numerous WBAN applications are highlighted