Wearable Chemical Sensors Research Articles

Advances in Wearable Smart Chemical Sensors for Health Monitoring

The advancement of wearable technology has entered a new phase, leading to the creation of various wearable sensors due to the rise of technologies like IoT and AI. Wearable chemical sensors are essential components of wearable electronics and hold significant promise in monitoring health. This review reports on the recent achievements and advantages of portable smart chemical sensing for health monitoring and discusses portable chemical sensing using frictional/piezoelectric electrochemical generators, photovoltaics and thermal power accumulators. This paper also evaluates the potential of wearable chemical sensors for health monitoring.

Current Trends and Challenges in Explosives Detection using Nanotechnology

Objective: This article highlights the applications of nanotechnology in the detection of explosives. Evidence acquisition: The increasing rise in terrorist acts throughout the globe has brought attention to the significance of locating hidden bombs and motivated new propelled breakthroughs to ensure public safety. Recognizing explosives and closely related-threatening combinations has already risen to the top of the priority list for contemporary national security and counterterrorism applications. Sensors based on nanotechnology have a fair probability of fulfilling all the criteria needed to be a practical solution for explosive trace detection. Results: Nanowire/nanotube, nanomechanical devices, and electronic noses are three nanosensor technologies that have the most potential to develop into commercially viable technology platforms for the detection of trace explosives. Certain functionalized nanoparticles can exhibit different behaviors as a result of unique interactions with nitroaromatics. Semiconducting singlewalled carbon nanotubes (SWCNT) have been used as wearable chemical sensors. Conclusion: In this paper, the potential of nanosensors has been exposed that can be used to build a sensor system with high selectivity and sensitivity and appropriate platforms for signal transduction for the detection of explosives.

Revolutionizing Personalized Health: The Frontier of Wearable Biomolecule Sensors Through 3D Printing Innovation

AbstractThis review article delves into the innovative intersection of 3D-printed technologies and wearable chemical sensors, highlighting a forward-thinking approach to biomarker monitoring. It emphasizes the transformative role of additive manufacturing in the development of wearable devices tailored for the precise detection of chemical biomarkers, crucial for proactive disease management and health assessment. By offering a detailed exploration of how 3D printing of nanomaterials contributes to pioneering sensor designs, this review underscores the practicality of sensor wearability, ensuring comfort and efficacy for users. We address the challenges of material resilience, sensor durability, and efficient data communication, while also charting the significant trends and future directions that promise to redefine the landscape of flexible and wearable chemical sensors. Through a comprehensive analysis, this article aims to showcase the pivotal advancements and ongoing innovations in the field, emphasizing the critical impact of 3D printing on enhancing personalized healthcare and wearable diagnostics. Graphical Abstract

Freestanding Films of Reduced Graphene Oxide Fully Decorated with Prussian Blue Nanoparticles for Hydrogen Peroxide Sensing.

Developing thin, freestanding electrodes that work simultaneously as a current collector and electroactive material is pivotal to integrating portable and wearable chemical sensors. Herein, we have synthesized graphene/Prussian blue (PB) electrodes for hydrogen peroxide detection (H2O2) using a two-step method. First, an reduced graphene oxide/PAni/Fe2O3 freestanding film is prepared using a doctor blade technique, followed by the electrochemical deposition of PB nanoparticles over the films. The iron oxide nanoparticles work as the iron source for the heterogeneous electrochemical deposition of the nanoparticles in a ferricyanide solution. The size of the PB cubes electrodeposited over the graphene-based electrodes was controlled by the number of voltammetric cycles. For H2O2 sensing, the PB10 electrode achieved the lowest detection and quantification limits, 2.00 and 7.00 μM, respectively. The findings herein evidence the balance between the structure of the graphene/PB-based electrodes with the electrochemical performance for H2O2 detection and pave the path for developing new freestanding electrodes for chemical sensors.

Intrinsically stretchable jellyfish-like gold nanowires film as multifunctional wearable chemical and physical sensors

We report on an intrinsically stretchable jellyfish-like gold nanowires film as a multifunctional wearable platform that can detect both chemical and physical biometrics. The film inherently exhibits multifunctionality, serving directly as an electrochemical electrode, strain sensor, temperature sensor, pressure sensor, and noncontact humidity sensor without the need of any additional materials. Our results highlight the excellent electrochemical properties, evidenced by a large electrochemical active surface area (EASA) of approximately 22.39 cm2 and the ability to withstand significant strain values up to 70 %. Leveraging these attributes, a stretchable electrochemical glucose biosensor was further designed with high sensitivity (45.40μA·mM−1·cm−2) and low limit of detection (10 μM). In addition, its sensing applications in strain, temperature, pressure and noncontact humidity were systematically explored. Impressively, the gold film is capable of monitoring multiple human motions and physiological signals, including joints bending, pulse motions, throat motions (e.g., drinking, speaking, swallowing and pronunciation recognition) and breathing. Furthermore, the film exhibited great versatility by integrating with 3D printing hydrogels, enabling customized patterning. The results demonstrate that our gold nanowires coating approach represent a new route to design multimodal soft wearable platforms for applications in personalized medicine and next-generation healthcare systems.

Wearable chemical gas sensors with color changeable functional dyes for detection of organophosphorus nerve agents

Wearable chemical gas sensors with color changeable functional dyes for detection of organophosphorus nerve agents

Textronic Solutions Used to Produce Layers Sensitive to Chemical Stimuli-Gas Sensors: A Review.

Thanks to the intensive development of textronics, textronic applications are already visible in many areas of everyday life. Many researchers around the world have focused on the invention of textronic systems to increase security, create technological innovations and make everyday life easier and more interesting. Due to the wide use of chemical textile sensors, this review article lists scientific publications covering all types of wearable chemical sensors along with their latest developments. The latest developments from the last few years in moisture, pH, sweat and biomolecules sensors are described. In this review, greatest emphasis and detail was placed on textile gas sensors and their production methods. The use of, among others, graphene and zinc oxide grown on cotton fabric, colorimetric textiles based on halochromic dye, electronic graphene fabric based on lotus fibers and graphene oxide and zinc oxide nanorods were considered. Finally, this article summarizes our current knowledge on gas sensors, compares the detection properties of the presented projects and indicates future directions of development.

Development of Wearable Chemical Sensors: An Interdisciplinary Undergraduate Laboratory Experiment Facilitating Knowledge and Expertise Integration

Development of Wearable Chemical Sensors: An Interdisciplinary Undergraduate Laboratory Experiment Facilitating Knowledge and Expertise Integration

Emerging Wearable Chemical Sensors Enabling Advanced Integrated Systems toward Personalized and Preventive Medicine.

ADVERTISEMENT RETURN TO ISSUEPREVReviewNEXTEmerging Wearable Chemical Sensors Enabling Advanced Integrated Systems toward Personalized and Preventive MedicineTianyiyi HeTianyiyi HeDepartment of Electrical and Computer Engineering, National University of Singapore, 4 Engineering Drive 3, Singapore 117583, SingaporeCenter for Intelligent Sensors and MEMS, National University of Singapore, Block E6 #05-11, 5 Engineering Drive 1, Singapore 117608, SingaporeMore by Tianyiyi HeView Biography, Feng WenFeng WenDepartment of Electrical and Computer Engineering, National University of Singapore, 4 Engineering Drive 3, Singapore 117583, SingaporeCenter for Intelligent Sensors and MEMS, National University of Singapore, Block E6 #05-11, 5 Engineering Drive 1, Singapore 117608, SingaporeMore by Feng WenView Biography, Yanqin YangYanqin YangDepartment of Electrical and Computer Engineering, National University of Singapore, 4 Engineering Drive 3, Singapore 117583, SingaporeCenter for Intelligent Sensors and MEMS, National University of Singapore, Block E6 #05-11, 5 Engineering Drive 1, Singapore 117608, SingaporeMore by Yanqin YangView Biography, Xianhao LeXianhao LeDepartment of Electrical and Computer Engineering, National University of Singapore, 4 Engineering Drive 3, Singapore 117583, SingaporeCenter for Intelligent Sensors and MEMS, National University of Singapore, Block E6 #05-11, 5 Engineering Drive 1, Singapore 117608, SingaporeMore by Xianhao LeView Biography, Weixin LiuWeixin LiuDepartment of Electrical and Computer Engineering, National University of Singapore, 4 Engineering Drive 3, Singapore 117583, SingaporeCenter for Intelligent Sensors and MEMS, National University of Singapore, Block E6 #05-11, 5 Engineering Drive 1, Singapore 117608, SingaporeMore by Weixin LiuView Biographyhttps://orcid.org/0000-0002-5526-3487, and Chengkuo Lee*Chengkuo LeeDepartment of Electrical and Computer Engineering, National University of Singapore, 4 Engineering Drive 3, Singapore 117583, SingaporeCenter for Intelligent Sensors and MEMS, National University of Singapore, Block E6 #05-11, 5 Engineering Drive 1, Singapore 117608, Singapore*[email protected]More by Chengkuo LeeView Biographyhttps://orcid.org/0000-0002-8886-3649Cite this: Anal. Chem. 2023, 95, 1, 490–514Publication Date (Web):January 10, 2023Publication History Received14 October 2022Published online10 January 2023Published inissue 10 January 2023https://doi.org/10.1021/acs.analchem.2c04527Copyright © 2023 American Chemical SocietyRIGHTS & PERMISSIONSArticle Views419Altmetric-Citations-LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InReddit Read OnlinePDF (5 MB) Get e-AlertsSUBJECTS:Anatomy,Carbohydrates,Sensors,Substrates,Wearable electronics Get e-Alerts

Wearable chemical sensors based on 2D materials for healthcare applications.

Chemical sensors worn on the body could make possible the continuous, noninvasive, and accurate monitoring of vital human signals, which is necessary for remote health monitoring and telemedicine. Attractive for creating high-performance, wearable chemical sensors are atomically thin materials with intriguing physical features, abundant chemistry, and high surface-to-volume ratios. These advantages allow for appropriate material-analyte interactions, resulting in a high level of sensitivity even at trace analyte concentrations. Previous review articles covered the material and device elements of 2D material-based wearable devices extensively. In contrast, little research has addressed the existing state, future outlook, and promise of 2D materials for wearable chemical sensors. We provide an overview of recent advances in 2D-material-based wearable chemical sensors to overcome this deficiency. The structure design, manufacturing techniques, and mechanisms of 2D material-based wearable chemical sensors will be evaluated, as well as their applicability in human health monitoring. Importantly, we present a thorough review of the current state of the art and the technological gaps that would enable the future design and nanomanufacturing of 2D materials and wearable chemical sensors. Finally, we explore the challenges and opportunities associated with designing and implementing 2D wearable chemical sensors.

Wearable chemical sensors for biomarker discovery in the omics era.

Biomarkers are crucial biological indicators in medical diagnostics and therapy. However, the process of biomarker discovery and validation is hindered by a lack of standardized protocols for analytical studies, storage and sample collection. Wearable chemical sensors provide a real-time, non-invasive alternative to typical laboratory blood analysis, and are an effective tool for exploring novel biomarkers in alternative body fluids, such as sweat, saliva, tears and interstitial fluid. These devices may enable remote at-home personalized health monitoring and substantially reduce the healthcare costs. This Review introduces criteria, strategies and technologies involved in biomarker discovery using wearable chemical sensors. Electrochemical and optical detection techniques are discussed, along with the materials and system-level considerations for wearable chemical sensors. Lastly, this Review describes how the large sets of temporal data collected by wearable sensors, coupled with modern data analysis approaches, would open the door for discovering new biomarkers towards precision medicine.

Analytisk kemi – några reflektioner

Analytical chemistry is an interdisciplinary field of science related to many practical applications, such as clinical diagnostics, environmental monitoring and industrial process analysis. Over the last 50 years, chemical analytics has evolved from centralized laboratory measurements towards on-line and distributed analysis, including wearable chemical sensors for personal health monitoring. In this article I wish to reflect upon these developments in analytical chemistry, illustrated by examples from my own research. The text provides a glimpse of analytical chemistry from my personal perspective.

Chemical sensing by interfacial voltage

Developing methods for chemical sensing is of importance in broad applications, including food safety, healthcare, and ecology. The work herein describes an approach to chemical sensing by interfacial voltage. A test electrode is coated with a dielectric and a receptor. When the test electrode contacts an electrolyte, the receptor adsorbs an analyte from the electrolyte. The adsorption generates an interfacial voltage, a measurement of which reports the concentration of the analyte. This design de-integrates two aspects of sensing: adsorption and detection. Consequently, the test electrode can be made of any electronic conductor. This flexibility enables sensors to be fabricated without microelectronic facilities. Several species of ions and organic molecules are detected, and a wearable chemical sensor worn on a fingertip is demonstrated. Needle-shaped electrodes are developed to test soft biological tissues. Chemical sensing by interfacial voltage holds promise for the development of ubiquitous sensing technology.

Reduced graphene oxide coated cotton e-textile for wearable chemical warfare agent sensors

A facile, safe, and scalable method for fabricating electrically conductive-reduced graphene oxide (rGO) e-fabric using a plasma-assisted coating process has been demonstrated. A wearable sensor based on rGO e-fabric was fabricated and used to detect and distinguish deadly chemical warfare agents (CWAs). The rGO e-fabric-based CWA sensor exhibited consistent responses upon repeated exposure to chemicals, including dimethyl methylphosphonate (DMMP) and soman (GD), which is a nerve agent. A difference in responses of the sensor toward GD and DMMP was observed. Theoretical studies further confirmed the potential of the as-prepared device as an e-fabric sensor for the detection of nerve agents. This novel functional e-fabric holds promise for future applications of wearable chemical agent sensors in smart personal protective suits.

Highly Scalable, Wearable Surface‐Enhanced Raman Spectroscopy

AbstractThe last two decades have witnessed a dramatic growth of wearable sensor technology, mainly represented by flexible, stretchable, on‐skin electronic sensors that provide rich information of the wearer's health conditions and surroundings. A recent breakthrough in the field is the development of wearable chemical sensors based on surface‐enhanced Raman spectroscopy (SERS) that can detect molecular fingerprints universally, sensitively, and noninvasively. However, while their sensing properties are excellent, these sensors are not scalable for widespread use beyond small‐scale human health monitoring due to their cumbersome fabrication process and limited multifunctional sensing capabilities. Here, a highly scalable, wearable SERS sensor is demonstrated based on an easy‐to‐fabricate, low‐cost, ultrathin, flexible, stretchable, adhesive, and biointegratable gold nanomesh. It can be fabricated in any shape and worn on virtually any surface for label‐free, large‐scale, in situ sensing of diverse analytes from low to high concentrations (10–106 × 10−9 m). To show the practical utility of the wearable SERS sensor, the sensor is tested for the detection of sweat biomarkers, drugs of abuse, and microplastics. This wearable SERS sensor represents a significant step toward the generalizability and practicality of wearable sensing technology.

Recent advances in flexible and wearable sensors for monitoring chemical molecules.

In recent years, real-time health management has received increasing attention, benefiting from the rapid development of flexible and wearable devices. Conventionally, flexible and wearable devices are used for collecting health data such as electrophysiological signals, blood pressure, heart rate, etc. The monitoring of chemical factors has shown growing significance, providing the basis for the screening, diagnosis, and treatment of many diseases. Nowadays, in order to understand the health status of the human body more comprehensively and accurately, researchers in the community have started putting effort into developing wearable devices for monitoring chemical factors. Progressively, more flexible chemical sensors with wearable real-time health-monitoring functionality have been developed thanks to advances relating to wireless communications and flexible electronics. In this review, we describe the variety of chemical molecules and information that can currently be monitored, including pH levels, glucose, lactate, uric acid, ion levels, cytokines, nutrients, and other biomarkers. This review analyzes the pros and cons of the most advanced wearable chemical sensors in terms of wearability. At the end of this review, we discuss the current challenges and development trends relating to flexible and wearable chemical sensors from the aspects of materials, electrode designs, and soft-hard interface connections.

Wearable humidity sensors based on bar-printed poly(ionic liquid) for real-time humidity monitoring systems

Wearable chemical sensors can provide crucial human-physiology information by monitoring humidity in various environments. Capacitive-type humidity sensors based on poly(ionic liquid) (PIL) as the sensing material, which was synthesized via the polymerization of an ionic liquid (IL) were developed. The PIL films fabricated through a facile bar-printing process in ambient air, exhibited outstanding capacitive characteristics over a broad relative humidity (RH) range of 10%−80% at frequencies between 100 Hz and 1 MHz. Notably, high sensitivity (1.8 nF/%RH), good linearity (R2 = 0.980), low hysteresis, and fast response (~20 ms) of the developed humidity sensors were achieved. The corresponding sensing mechanism of the PIL for capacitive-type humidity sensors was studied by investigating the chemisorption of water molecules on the PIL surface and proton hopping through multiple layers of water molecules physisorbed on chemisorbed water molecules through single hydrogen bonding. In addition, the operational stability of the wearable humidity sensors developed in this study was investigated by analyzing the capacitive characteristics of the PIL sensing material at various temperatures (20–60 °C), even under a bending state and after 20,000 bending-stress cycles with a strain of 30%. Finally, a real-time humidity monitoring system integrated with signal processing and wireless communication modules was demonstrated by analyzing real-time capacitive signals acquired from a wearable humidity sensor attached to a human wrist and by visualizing processed humidity information on a user’s smartphone.

Printed circuit board integrated wearable ion-selective electrode with potential treatment for highly repeatable sweat monitoring

Wearable chemical sensors have recently received great attention, especially on monitoring ion concentration in sweat. However, challenges still remain, such as the nonnegligible potential deviation of the ion-selective electrode (ISE) based potentiometric sensor after multi-use. Herein, we propose an easily prepared and highly integrated wearable solid contact-ISE (SC-ISE), allowing multiple measurements with repeatable open circuit potential (OCP), which is achieved by applying a positive potential on the working electrode. It’s believed that the positive potential alters the oxidation-reduction state of the conducting polymer. The integrated SC-ISE sensor is fabricated on a printed circuit board (PCB) substrate, eliminating external hardware. Preparation of the sensor electrode adopts a standard route, i.e. employing the electroless nickel immersion gold (ENIG) process for plating gold layers. Dual working electrodes have been designed to measure either sodium or potassium ion. This wearable platform has been validated through on-body tests by monitoring ion levels in the real sweat.

(Plenary) Wearable Sensors for Monitoring Chemical Markers: Beyond Steps and Vitals

Wearable sensors have received a major recent attention owing to their considerable promise for monitoring the wearer's health and wellness. The medical interest for wearable systems arises from the need for monitoring patients over long periods of time. These devices have the potential to continuously collect vital health information from a person's body and provide this information to them or their healthcare provider in a timely fashion. Unlike early efforts aimed at monitoring mobility and vital signs, our recent efforts aim at filling the gaps by providing continuous biochemical information. The new chemical sensing wearable platforms provide new avenues to continuously and non-invasively monitor individuals and can thus tender crucial real-time information regarding a wearer's health. This presentation will discuss recent developments in the field of wearable electrochemical sensors integrated directly on the epidermis or within the mouth for various non-invasive biomedical monitoring applications [1-3]. Particular attention will be given to non-invasive monitoring of metabolites and electrolytes using flexible amperometric and potentiometric sensors, respectively, along with related materials, energy and integration considerations. Microneedle sensor arrays for multiplexed ISF monitoring will also be discussed also with wearable energy harvesters aimed to power these devices. The preparation and characterization of such wearable electrochemical sensors will be described, along with their current status and future prospects and challenges.REFERENCES[1] "Wearable Chemical Sensors: Present Challenges and Future Prospects" A. J. Bandodkar, I. Jeerapan, J. Wang, ACS Sensors, 2016, 1, 464.[2] A. J. Bandodkar and J. Wang, "Non-invasive wearable electrochemical sensors: a review", Trends Biotechnol., 2014, 32, 363.[3] "Wearable biosensors for healthcare monitoring", J. Kim, A. S. Campbell, B. Esteban-Fernández de Ávila, and J. Wang, Nature Biotechnology, 2019, 37, 389.

Fabrication of Graphene Based Durable Intelligent Personal Protective Clothing for Conventional and Non-Conventional Chemical Threats.

Conventional or non-conventional chemical threat is gaining huge attention due to its unpredictable and mass destructive effects. Typical military protective suits have drawbacks such as high weight, bulky structure, and unpredictable lifetime. A durable, light, and scalable graphene e-fabric was fabricated from CVD-grown graphene by a simple co-lamination method. The sheet resistance was below 1 kΩ/sq over the wide surface area even after 1000 bending cycles. A graphene triboelectric nanogenerator showed the peak VOC of 68 V and the peak ICC of 14.4 μA and 1 μF capacitor was charged successfully in less than 1 s. A wearable chemical sensor was also fabricated and showed a sensitivity up to 53% for nerve chemical warfare agents (GD). DFT calculations were conducted to unveil the fundamental mechanisms underlying the graphene e-fabric sensor. Additionally, protection against chemical warfare agents was tested, and a design concept of graphene-based intelligent protective clothing has been proposed.