@article{jamalzadegan_kim_mohammad_koduri_hetzler_lee_dickey_wei_2024, title={Liquid Metal-Based Biosensors: Fundamentals and Applications}, volume={1}, ISSN={["1616-3028"]}, url={https://doi.org/10.1002/adfm.202308173}, DOI={10.1002/adfm.202308173}, abstractNote={AbstractBiosensors are analytical tools for monitoring various parameters related to living organisms, such as humans and plants. Liquid metals (LMs) have emerged as a promising new material for biosensing applications in recent years. LMs have attractive physical and chemical properties such as deformability, high thermal and electrical conductivity, low volatility, and low viscosity. LM‐based biosensors represent a new strategy in biosensing particularly for wearable and real‐time sensing. While early demonstrations of LM biosensors focus on monitoring physical parameters such as strain, motion, and temperature, recent examples show LM can be an excellent sensing material for biochemical and biomolecular detection as well. In this review, the recent progress of LM‐based biosensors for personalized healthcare and disease monitoring via both physical and biochemical signaling is survey. It is started with a brief introduction of the fundamentals of biosensors and LMs, followed by a discussion of different mechanisms by which LM can transduce biological or physiological signals. Next, it is reviewed example LM‐based biosensors that have been used in real biological systems, ranging from real‐time on‐skin physiological monitoring to target‐specific biochemical detection. Finally, the challenges and future directions of LM‐integrated biosensor platforms is discussed.}, journal={ADVANCED FUNCTIONAL MATERIALS}, author={Jamalzadegan, Sina and Kim, Sooyoung and Mohammad, Noor and Koduri, Harshita and Hetzler, Zach and Lee, Giwon and Dickey, Michael D. and Wei, Qingshan}, year={2024}, month={Jan} }
 @article{lee_hossain_jamalzadegan_liu_wang_saville_shymanovich_paul_rotenberg_whitfield_et al._2023, title={Abaxial leaf surface-mounted multimodal wearable sensor for continuous plant physiology monitoring}, volume={9}, ISSN={["2375-2548"]}, DOI={10.1126/sciadv.ade2232}, abstractNote={Wearable plant sensors hold tremendous potential for smart agriculture. We report a lower leaf surface-attached multimodal wearable sensor for continuous monitoring of plant physiology by tracking both biochemical and biophysical signals of the plant and its microenvironment. Sensors for detecting volatile organic compounds (VOCs), temperature, and humidity are integrated into a single platform. The abaxial leaf attachment position is selected on the basis of the stomata density to improve the sensor signal strength. This versatile platform enables various stress monitoring applications, ranging from tracking plant water loss to early detection of plant pathogens. A machine learning model was also developed to analyze multichannel sensor data for quantitative detection of tomato spotted wilt virus as early as 4 days after inoculation. The model also evaluates different sensor combinations for early disease detection and predicts that minimally three sensors are required including the VOC sensors.}, number={15}, journal={SCIENCE ADVANCES}, author={Lee, Giwon and Hossain, Oindrila and Jamalzadegan, Sina and Liu, Yuxuan and Wang, Hongyu and Saville, Amanda C. and Shymanovich, Tatsiana and Paul, Rajesh and Rotenberg, Dorith and Whitfield, Anna E. and et al.}, year={2023}, month={Apr} }
 @article{son_lee_wang_samson_wei_zhu_you_2022, title={Integrating charge mobility, stability and stretchability within conjugated polymer films for stretchable multifunctional sensors}, volume={13}, ISSN={["2041-1723"]}, url={https://doi.org/10.1038/s41467-022-30361-0}, DOI={10.1038/s41467-022-30361-0}, abstractNote={AbstractConjugated polymers (CPs) are promising semiconductors for intrinsically stretchable electronic devices. Ideally, such CPs should exhibit high charge mobility, excellent stability, and high stretchability. However, converging all these desirable properties in CPs has not been achieved via molecular design and/or device engineering. This work details the design, synthesis and characterization of a random polythiophene (RP-T50) containing ~50 mol% of thiophene units with a thermocleavable tertiary ester side chain and ~50 mol% of unsubstituted thiophene units, which, upon thermocleavage of alkyl chains, shows significant improvement of charge mobility and stability. Thermal annealing a RP-T50 film coated on a stretchable polydimethylsiloxane substrate spontaneously generates wrinkling in the polymer film, which effectively enhances the stretchability of the polymer film. The wrinkled RP-T50-based stretchable sensors can effectively detect humidity, ethanol, temperature and light even under 50% uniaxial and 30% biaxial strains. Our discoveries offer new design rationale of strategically applying CPs to intrinsically stretchable electronic systems.}, number={1}, journal={NATURE COMMUNICATIONS}, author={Son, Sung Yun and Lee, Giwon and Wang, Hongyu and Samson, Stephanie and Wei, Qingshan and Zhu, Yong and You, Wei}, year={2022}, month={May} }
 @article{lee_zarei_wei_zhu_lee_2022, title={Surface Wrinkling for Flexible and Stretchable Sensors}, volume={9}, ISSN={["1613-6829"]}, url={https://doi.org/10.1002/smll.202203491}, DOI={10.1002/smll.202203491}, abstractNote={AbstractRecent advances in nanolithography, miniaturization, and material science, along with developments in wearable electronics, are pushing the frontiers of sensor technology into the large‐scale fabrication of highly sensitive, flexible, stretchable, and multimodal detection systems. Various strategies, including surface engineering, have been developed to control the electrical and mechanical characteristics of sensors. In particular, surface wrinkling provides an effective alternative for improving both the sensing performance and mechanical deformability of flexible and stretchable sensors by releasing interfacial stress, preventing electrical failure, and enlarging surface areas. In this study, recent developments in the fabrication strategies of wrinkling structures for sensor applications are discussed. The fundamental mechanics, geometry control strategies, and various fabricating methods for wrinkling patterns are summarized. Furthermore, the current state of wrinkling approaches and their impacts on the development of various types of sensors, including strain, pressure, temperature, chemical, photodetectors, and multimodal sensors, are reviewed. Finally, existing wrinkling approaches, designs, and sensing strategies are extrapolated into future applications.}, journal={SMALL}, author={Lee, Giwon and Zarei, Mohammad and Wei, Qingshan and Zhu, Yong and Lee, Seung Goo}, year={2022}, month={Sep} }
 @article{lee_wei_zhu_2021, title={Emerging Wearable Sensors for Plant Health Monitoring}, volume={10}, ISSN={["1616-3028"]}, DOI={10.1002/adfm.202106475}, abstractNote={AbstractEmerging plant diseases, caused by pathogens, pests, and climate change, are critical threats to not only the natural ecosystem but also human life. To mitigate crop loss due to various biotic and abiotic stresses, new sensor technologies to monitor plant health, predict, and track plant diseases in real time are desired. Wearable electronics have recently been developed for human health monitoring. However, the application of wearable electronics to agriculture and plant science is in its infancy. Wearable technologies mean that the sensors will be directly placed on the surfaces of plant organs such as leaves and stems. The sensors are designed to detect the status of plant health by profiling various trait biomarkers and microenvironmental parameters, transducing bio‐signals to electric readout for data analytics. In this perspective, the recent progress in wearable plant sensors is summarized and they are categorized by the functionality, namely plant growth sensors, physiology, and microclimate sensors, chemical sensors, and multifunctional sensors. The design and mechanism of each type of wearable sensors are discussed and their applications to address the current challenges of precision agriculture are highlighted. Finally, challenges and perspectives for the future development of wearable plant sensors are presented.}, journal={ADVANCED FUNCTIONAL MATERIALS}, author={Lee, Giwon and Wei, Qingshan and Zhu, Yong}, year={2021}, month={Oct} }