@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{wang_pirzada_xie_barbieri_hossain_opperman_pal_wei_parsons_khan_2022, title={Creating hierarchically porous banana paper-metal organic framework (MOF) composites with multifunctionality}, volume={28}, ISSN={["2352-9407"]}, url={https://doi.org/10.1016/j.apmt.2022.101517}, DOI={10.1016/j.apmt.2022.101517}, abstractNote={We report a robust approach to integrate metal-organic frameworks (MOF) via vapor phase synthesis on a cost-effective and mechanically durable fibrous banana paper (BP) substrate developed from lignocellulosic biomass. The unique hollow fibrous structure of BP combined with the methodology used produces MOF-fiber composites with uniform MOF distribution and enhanced functionalities, with minimal use of organic solvents. The BP-MOF composites demonstrate a high surface area of 552 m2/g and uniform surface growth of MOF on them. Mechanical strength and bending flexibility of the substrate is well retained after the MOF growth, while the hollow tubular nature and hierarchical porosity of the BP facilitate gas diffusion. The BP-MOF composites demonstrate strong antibacterial activity with 99.2% of E.coli destroyed within the first hour of incubation. Preliminary studies with smartphone-based volatile organic compound (VOC) sensor show enhanced 1-octen-3-ol vapor absorption on BP-MOF, indicating its potential for VOC capture and sensing. We believe that the sustainable nature and flexibility of the lignocellulosic BP substrate taken together with uniform growth of MOF on the hierarchically porous BP impart impressive attributes to these composites, which can be explored in diverse applications.}, journal={APPLIED MATERIALS TODAY}, publisher={Elsevier BV}, author={Wang, Siyao and Pirzada, Tahira and Xie, Wenyi and Barbieri, Eduardo and Hossain, Oindrila and Opperman, Charles H. and Pal, Lokendra and Wei, Qingshan and Parsons, Gregory N. and Khan, Saad A.}, year={2022}, month={Aug} }
 @misc{silva_tomlinson_onkokesung_sommer_mrisho_legg_adams_gutierrez-vazquez_howard_laverick_et al._2021, title={Plant pest surveillance: from satellites to molecules}, volume={5}, ISSN={["2397-8562"]}, DOI={10.1042/ETLS20200300}, abstractNote={Plant pests and diseases impact both food security and natural ecosystems, and the impact has been accelerated in recent years due to several confounding factors. The globalisation of trade has moved pests out of natural ranges, creating damaging epidemics in new regions. Climate change has extended the range of pests and the pathogens they vector. Resistance to agrochemicals has made pathogens, pests, and weeds more difficult to control. Early detection is critical to achieve effective control, both from a biosecurity as well as an endemic pest perspective. Molecular diagnostics has revolutionised our ability to identify pests and diseases over the past two decades, but more recent technological innovations are enabling us to achieve better pest surveillance. In this review, we will explore the different technologies that are enabling this advancing capability and discuss the drivers that will shape its future deployment.}, number={2}, journal={EMERGING TOPICS IN LIFE SCIENCES}, author={Silva, Goncalo and Tomlinson, Jenny and Onkokesung, Nawaporn and Sommer, Sarah and Mrisho, Latifa and Legg, James and Adams, Ian P. and Gutierrez-Vazquez, Yaiza and Howard, Thomas P. and Laverick, Alex and et al.}, year={2021}, pages={275–287} }
 @article{li_liu_hossain_paul_yao_wu_ristaino_zhu_wei_2021, title={Real-time monitoring of plant stresses via chemiresistive profiling of leaf volatiles by a wearable sensor}, volume={4}, ISSN={["2590-2385"]}, DOI={10.1016/j.matt.2021.06.009}, abstractNote={•We report a leaf-attachable VOC sensor for real-time profiling of plant volatiles•The sensor patch detects plant VOCs at low-ppm concentrations•13 individual plant VOCs were differentiated with >97% accuracy by the sensor•It has been used to detect tomato late blight and mechanical damage noninvasively Developing a noninvasive sensing technique that enables continuous plant volatile organic compound (VOC) analysis in their natural habitat is essential to capture the VOC flux from plants for accurate monitoring of plant diseases and stresses. Several wearable sensor platforms have recently been developed that can be attached to living plants for continuous monitoring. However, detecting and discrimination of plant chemical cues such as VOCs have rarely been reported by using a wearable sensor platform. Here, a real-time VOC-profiling sensor device on a stretchable substrate has been developed for instant monitoring of plant host responses for early disease diagnosis and rapid stress identification of living plants. Determination of plant stresses such as infections by plant pathogens is currently dependent on time-consuming and complicated analytical technologies. Here, we report a leaf-attachable chemiresistive sensor array for real-time fingerprinting of volatile organic compounds (VOCs) that permits noninvasive and early diagnosis of plant diseases, such as late blight caused by Phytophthora infestans. The imperceptible sensor patch integrates an array of graphene-based sensing materials and flexible silver nanowire electrodes on a kirigami-inspired stretchable substrate, which can minimize strain interference. The sensor patch has been mounted on live tomato plants to profile key plant volatiles at low-ppm concentrations with fast response (<20 s). The multiplexed sensor array allows for accurate detection and classification of 13 individual plant volatiles with >97% classification accuracy. The wearable sensor patch was used to diagnose tomato late blight as early as 4 days post inoculation and abiotic stresses such as mechanical damage within 1 h. Determination of plant stresses such as infections by plant pathogens is currently dependent on time-consuming and complicated analytical technologies. Here, we report a leaf-attachable chemiresistive sensor array for real-time fingerprinting of volatile organic compounds (VOCs) that permits noninvasive and early diagnosis of plant diseases, such as late blight caused by Phytophthora infestans. The imperceptible sensor patch integrates an array of graphene-based sensing materials and flexible silver nanowire electrodes on a kirigami-inspired stretchable substrate, which can minimize strain interference. The sensor patch has been mounted on live tomato plants to profile key plant volatiles at low-ppm concentrations with fast response (<20 s). The multiplexed sensor array allows for accurate detection and classification of 13 individual plant volatiles with >97% classification accuracy. The wearable sensor patch was used to diagnose tomato late blight as early as 4 days post inoculation and abiotic stresses such as mechanical damage within 1 h. Phytophthora infestans is the causal agent of late blight and one of the most destructive diseases of economically important crops such as tomato and potato.1Ristaino J.B. Cooke D.E.L. Acuña I. Muñoz M. The threat of late blight to global food security.in: Ristaino J.B. Records A. Emerging Plant Diseases and Global Food Security. 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On the other hand, detection and discrimination of chemical or biological signals has not been fully explored by using a plant-wearable sensor. Lee et al. reported a carbon nanotube-based wearable field-effect transistor device for gas sensing on the surface of plant leaves.53Lee K. Park J. Lee M.S. Kim J. Hyun B.G. Kang D.J. Na K. Lee C.Y. Bien F. Park J.U. In-situ synthesis of carbon nanotube-graphite electronic devices and their integrations onto surfaces of live plants and insects.Nano Let. 2014; 14: 2647-2654Crossref PubMed Scopus (72) Google Scholar However, only simulant gas molecules such as dimethyl methylphosphonate but no actual plant VOCs has been analyzed using the wearable sensor. As such, a wearable sensor platform that can measure VOC emissions from plants in real time is urgently needed to ensure the early detection of plant diseases or stresses. In this work, we demonstrate a wearable sensor platform for real-time profiling of plant VOC markers based on a chemiresistive sensor array made of reduced graphene oxide (rGO) functionalized with various ligands (Figure 1). This multiplexed sensor array includes two different types of rGO sensors that can form reversible interactions with various plant VOCs via either hydrogen or halogen bonding. The rGO nanosheets are modified either with functionalized gold nanoparticles (AuNPs) or directly with chemical ligands containing different recognition groups (Figure S1B) to selectively capture oxygen- or nitrogen-containing organic compounds (e.g., aldehydes, ketones, alcohols) from a wide variety of plant VOCs (Figure S1A).26Weis J.G. Ravnsbæk J.B. Mirica K.A. Swager T.M. Employing halogen bonding interactions in chemiresistive gas sensors.ACS Sens. 2015; 1: 115-119Crossref Scopus (39) Google Scholar,54Frazier K.M. Swager T.M. Robust cyclohexanone selective chemiresistors based on single-walled carbon nanotubes.Anal. Chem. 2013; 85: 7154-7158Crossref PubMed Scopus (36) Google Scholar,55Jaini A.K.A. Hughes L.B. Kitimet M.M. Ulep K.J. Leopold M.C. Parish C.A. Halogen bonding interactions for aromatic and nonaromatic explosive detection.ACS Sens. 2019; 4: 389-397Crossref PubMed Scopus (16) Google Scholar The optimized sensor array composed of 4–8 rGO sensors exhibits excellent discrimination results among different individual plant VOCs, such as green leaf volatiles (GLVs) and phytohormones under ambient conditions. The sensor patch was insensitive to common mechanical perturbations such as wind blowing and hand touching as a result of the stretchable kirigami-based substrate. The environmental perturbations from temperature and humidity were also investigated. 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We tested four potential carbon substrates in response to 10 ppm (E)-2-hexenal, a C6 GLV known as a VOC biomarker for late blight.18Laothawornkitkul J. Jansen R.M.C. Smid H.M. Bouwmeester H.J. Muller J. van Bruggen A.H.C. Volatile organic compounds as a diagnostic marker of late blight infected potato plants: a pilot study.Crop Prot. 2010; 29: 872Crossref Scopus (26) Google Scholar All carbon nanomaterials were functionalized with 1,3-dis[3,5-bis(trifluoromethyl)phenyl]thiourea (or thiourea for short), a chemical selector reported to form strong hydrogen bonds with electronegative elements such as carbonyl oxygen (Figure 1B).54Frazier K.M. Swager T.M. Robust cyclohexanone selective chemiresistors based on single-walled carbon nanotubes.Anal. Chem. 2013; 85: 7154-7158Crossref PubMed Scopus (36) Google Scholar Sensor elements were placed in a three-dimensional (3D)-printed gas chamber (4 × 3 × 1.2 cm) for sensing performance characterization using a three-way gas-mixing setup (Figure S2). We demonstrated that rGO showed the optimal and most reproducible sensor responses compared with graphene oxide (GO) and single-walled or multiwalled carbon nanotubes (SWCNTs or MWCNTs, respectively; Figure S3). Trends in the sensor response are consistent with the chemical and physical properties of different carbon materials: compared with GO and MWCNTs, rGO and SWCNTs have higher conductivity, larger surface areas, and less discrepancy in surface chemistry (higher product purity). As a comparison, pristine rGO without any surface functionalization showed nearly no response to the gas analyte (Figure S4). This result confirms that the specificity of the rGO sensors truly comes from the functional chemical ligands and therefore reduces the possible interference from the rGO itself. The mass ratio between thiourea ligand and rGO (mthiourea:mrGO) also affects the sensing performance. We found that 16.7 wt % of thiourea in the [email protected] hybrids produced the largest signal response (Figure S5), which was used for all subsequent studies. We then examined the sensing performance of the [email protected] sensor toward four model plant VOCs, namely (E)-2-hexenal, 1-hexenal, methyl jasmonate, and 2-phenylethanol, which have been reported as potential VOC diagnostic markers of P. infestans-infected tomato plants.18Laothawornkitkul J. Jansen R.M.C. Smid H.M. Bouwmeester H.J. Muller J. van Bruggen A.H.C. Volatile organic compounds as a diagnostic marker of late blight infected potato plants: a pilot study.Crop Prot. 2010; 29: 872Crossref Scopus (26) Google Scholar The four model VOCs differ in multiple physical and chemical properties such as polarity, hydrophilicity, and nucleophilicity of particular atoms or functional groups, which reflects the complicated nature of emitted plant VOC mixtures under different stresses. The [email protected] sensor displayed a quick response within the first 20 s of exposure (i.e., >90% of equilibrated response), and the positive electrical responses were totally reversible after purging with N2 (Figure 2A). The electric resistance of [email protected] sensor presented a nearly linear dependence on VOC concentrations (Figure S6A), with a limit of detection (LOD) ranging from ∼0.13 ppm to 1.4 ppm (Figure S6B). Compared with our previously reported colorimetric sensor array,34Li Z. Paul R. Ba Tis T. Saville A.C. Hansel J.C. Yu T. Ristaino J.B. Wei Q. Non-invasive plant disease diagnostics enabled by smartphone-based fingerprinting of leaf volatiles.Nat. Plants. 2019; 5: 856-866Crossref PubMed Scopus (87) Google Scholar the LODs of the wearable VOC sensors were improved by 2- to 10-fold for all tested VOCs except for (E)-2-hexenal (Figure S6B). To enhance the chemical diversity of the sensor array, we also integrated [email protected] sensors based on halogen or hydrogen interactions with plant VOCs (Figure 1B). Six probe molecules (Figure S1B), including four halothiophenols (ITP [iodothiophenol], BPT [bromothiophenol], CTP [chlorothiophenol], and FTP [fluorothiophenol]), a nitrothiophenol (NTP; hydrogen interaction), and a methoxythiophenol (MTP; control) were first attached to the surface of AuNPs (Figure 1B), and then mixed thoroughly with rGO substrates using the ball-milling technique. It has been reported that halogen-bonding interactions can be formed between electropositive aryl halide-based selectors and electron donors such as pyridine or pyrrole, which induces negative changes in resistance as opposed to positive changes obtained by the [email protected] sensor.26Weis J.G. Ravnsbæk J.B. Mirica K.A. Swager T.M. Employing halogen bonding interactions in chemiresistive gas sensors.ACS Sens. 2015; 1: 115-119Crossref Scopus (39) Google Scholar Since most plant VOCs are abundant in nitrogen- or oxygen-containing functional groups, those hydrogen or halogen-bonding mechanisms could possibly be applied for the recognition of multiple structurally similar plant VOCs. The mixing ratio of [email protected] with the rGO substrate again has been optimized, which was determined to be 9.1 wt % of capped AuNPs f}, number={7}, journal={MATTER}, author={Li, Zheng and Liu, Yuxuan and Hossain, Oindrila and Paul, Rajesh and Yao, Shanshan and Wu, Shuang and Ristaino, Jean B. and Zhu, Yong and Wei, Qingshan}, year={2021}, month={Jul}, pages={2553–2570} }
 @misc{tholl_hossain_weinhold_rose_wei_2021, title={Trends and applications in plant volatile sampling and analysis}, volume={106}, ISSN={["1365-313X"]}, DOI={10.1111/tpj.15176}, abstractNote={Volatile organic compounds (VOCs) released by plants serve as information and defense chemicals in mutualistic and antagonistic interactions and mitigate effects of abiotic stress. Passive and dynamic sampling techniques combined with gas chromatography–mass spectrometry analysis have become routine tools to measure emissions of VOCs and determine their various functions. More recently, knowledge of the roles of plant VOCs in the aboveground environment has led to the exploration of similar functions in the soil and rhizosphere. Moreover, VOC patterns have been recognized as sensitive and time-dependent markers of biotic and abiotic stress. This focused review addresses these developments by presenting recent progress in VOC sampling and analysis. We show advances in the use of small, inexpensive sampling devices and describe methods to monitor plant VOC emissions in the belowground environment. We further address latest trends in real-time measurements of volatilomes in plant phenotyping and most recent developments of small portable devices and VOC sensors for non-invasive VOC fingerprinting of plant disease. These technologies allow for innovative approaches to study plant VOC biology and application in agriculture.}, number={2}, journal={PLANT JOURNAL}, author={Tholl, Dorothea and Hossain, Oindrila and Weinhold, Alexander and Rose, Ursula S. R. and Wei, Qingshan}, year={2021}, month={Apr}, pages={314–325} }