Advances in Electronic-Nose Technologies Developed for Biomedical Applications

The research and development of new electronic-nose applications in the biomedical field has accelerated at a phenomenal rate over the past 25 years. Many innovative e-nose technologies have provided solutions and applications to a wide variety of complex biomedical and healthcare problems. The purposes of this review are to present a comprehensive analysis of past and recent biomedical research findings and developments of electronic-nose sensor technologies, and to identify current and future potential e-nose applications that will continue to advance the effectiveness and efficiency of biomedical treatments and healthcare services for many years. An abundance of electronic-nose applications has been developed for a variety of healthcare sectors including diagnostics, immunology, pathology, patient recovery, pharmacology, physical therapy, physiology, preventative medicine, remote healthcare, and wound and graft healing. Specific biomedical e-nose applications range from uses in biochemical testing, blood-compatibility evaluations, disease diagnoses, and drug delivery to monitoring of metabolic levels, organ dysfunctions, and patient conditions through telemedicine. This paper summarizes the major electronic-nose technologies developed for healthcare and biomedical applications since the late 1980s when electronic aroma detection technologies were first recognized to be potentially useful in providing effective solutions to problems in the healthcare industry

Diverse Applications of Electronic-Nose Technologies in Agriculture and Forestry

Electronic-nose (e-nose) instruments, derived from numerous types of aroma-sensor technologies, have been developed for a diversity of applications in the broad fields of agriculture and forestry. Recent advances in e-nose technologies within the plant sciences, including improvements in gas-sensor designs, innovations in data analysis and pattern-recognition algorithms, and progress in material science and systems integration methods, have led to significant benefits to both industries. Electronic noses have been used in a variety of commercial agricultural-related industries, including the agricultural sectors of agronomy, biochemical processing, botany, cell culture, plant cultivar selections, environmental monitoring, horticulture, pesticide detection, plant physiology and pathology. Applications in forestry include uses in chemotaxonomy, log tracking, wood and paper processing, forest management, forest health protection, and waste management. These aroma-detection applications have improved plant-based product attributes, quality, uniformity, and consistency in ways that have increased the efficiency and effectiveness of production and manufacturing processes. This paper provides a comprehensive review and summary of a broad range of electronic-nose technologies and applications, developed specifically for the agriculture and forestry industries over the past thirty years, which have offered solutions that have greatly improved worldwide agricultural and agroforestry production systems

Advances in Electronic-Nose Technologies for the Detection of Volatile Biomarker Metabolites in the Human Breath

Recent advancements in the use of electronic-nose (e-nose) devices to analyze human breath profiles for the presence of specific volatile metabolites, known as biomarkers or chemical bio-indicators of specific human diseases, metabolic disorders and the overall health status of individuals, are providing the potential for new noninvasive tools and techniques useful to point-of-care clinical disease diagnoses. This exciting new area of electronic disease detection and diagnosis promises to yield much faster and earlier detection of human diseases and disorders, allowing earlier, more effective treatments, resulting in more rapid patient recovery from various afflictions. E-nose devices are particularly suited for the field of disease diagnostics, because they are sensitive to a wide range of volatile organic compounds (VOCs) and can effectively distinguish between different complex gaseous mixtures via analysis of electronic aroma sensor-array output profiles of volatile metabolites present in the human breath. This review provides a summary of some recent developments of electronic-nose technologies, particularly involving breath analysis, with the potential for providing many new diagnostic applications for the detection of specific human diseases associated with different organs in the body, detectable from e-nose analyses of aberrant disease-associated VOCs present in air expired from the lungs

Differences in VOC-Metabolite Profiles of Pseudogymnoascus destructans and Related Fungi by Electronic-nose/GC Analyses of Headspace Volatiles Derived from Axenic Cultures

The most important disease affecting hibernating bats in North America is White-nose syndrome (WNS), caused by the psychrophilic fungal dermatophyte Pseudogymnoascus destructans. The identification of dermatophytic fungi, present on the skins of cave-dwelling bat species, is necessary to distinguish between pathogenic (disease-causing) microbes from those that are innocuous. This distinction is an important step for the early detection and identification of microbial pathogens on bat skin prior to the initiation of disease and symptom development, for the discrimination between specific microbial species interacting on the skins of hibernating bats, and for early indications of potential WNS-disease development based on inoculum potential. Early detection of P. destructans infections of WNS-susceptible bats, prior to symptom development, is essential to provide effective early treatments of WNS-diseased bats which could significantly improve their chances of survival and recovery. Current diagnostic methods using quantitative polymerase chain reaction (qPCR) for the targeted detection of specific fungal pathogens on bats require semi- invasive methods (skin swabs) that tend to arouse hibernating bats resulting in consumption of valuable fat reserves that reduce their chances of winter survival. Also, qPCR only indicates the presence and quantity (fungal loads) of specific fungal inoculum on bat skin, but does not conclusively indicate that the fungus has infected the host, or that a disease state exists, since template fungal DNA used for PCR comes from outside of the host rather than from within the host. Consequently, we are developing non-invasive methods for the early detection of WNS-disease based on the production of unique mixtures of volatile organic metabolites detected in sampled air (in proximity to bats) using a dual-technology, electronic-nose/gas chromatography device. This approach initially was tested in the current study to evaluate the potential of e-nose tools for identifying and discriminatin

Differences in VOC-Metabolite Profiles of Pseudogymnoascus destructans and Related Fungi by Electronic-nose/GC Analyses of Headspace Volatiles Derived from Axenic Cultures

The most important disease affecting hibernating bats in North America is White-nose syndrome (WNS), caused by the psychrophilic fungal dermatophyte Pseudogymnoascus destructans. The identification of dermatophytic fungi, present on the skins of cave-dwelling bat species, is necessary to distinguish between pathogenic (disease-causing) microbes from those that are innocuous. This distinction is an important step for the early detection and identification of microbial pathogens on bat skin prior to the initiation of disease and symptom development, for the discrimination between specific microbial species interacting on the skins of hibernating bats, and for early indications of potential WNS-disease development based on inoculum potential. Early detection of P. destructans infections of WNS-susceptible bats, prior to symptom development, is essential to provide effective early treatments of WNS-diseased bats which could significantly improve their chances of survival and recovery. Current diagnostic methods using quantitative polymerase chain reaction (qPCR) for the targeted detection of specific fungal pathogens on bats require semi- invasive methods (skin swabs) that tend to arouse hibernating bats resulting in consumption of valuable fat reserves that reduce their chances of winter survival. Also, qPCR only indicates the presence and quantity (fungal loads) of specific fungal inoculum on bat skin, but does not conclusively indicate that the fungus has infected the host, or that a disease state exists, since template fungal DNA used for PCR comes from outside of the host rather than from within the host. Consequently, we are developing non-invasive methods for the early detection of WNS-disease based on the production of unique mixtures of volatile organic metabolites detected in sampled air (in proximity to bats) using a dual-technology, electronic-nose/gas chromatography device. This approach initially was tested in the current study to evaluate the potential of e-nose tools for identifying and discriminatin

Detection of Off-Flavor in Catfish Using a Conducting Polymer Electronic-Nose Technology

The Aromascan A32S conducting polymer electronic nose was evaluated for the capability of detecting the presence of off-flavor malodorous compounds in catfish meat fillets to assess meat quality for potential merchantability. Sensor array outputs indicated that the aroma profiles of good-flavor (on-flavor) and off-flavor fillets were strongly different as confirmed by a Principal Component Analysis (PCA) and a Quality Factor value (QF > 7.9) indicating a significant difference at (P < 0.05). The A32S e-nose effectively discriminated between good-flavor and off-flavor catfish at high levels of accuracy (>90%) and with relatively low rates (≤5%) of unknown or indecisive determinations in three trials. This A32S e-nose instrument also was capable of detecting the incidence of mild off-flavor in fillets at levels lower than the threshold of human olfactory detection. Potential applications of e-nose technologies for pre- and post-harvest management of production and meat-quality downgrade problems associated with catfish off-flavor are discussed

Growth and competitive abilities of the federally endangered Lindera melissifolia and the potentially invasive Brunnichia ovata in varying densities, hydrologic regimes, and light availabilities.

Brunnichia ovata is a native, perennial, woody vine with the potential to become an aggressive competitor of the federally endangered shrub Lindera melissifolia. Our study simulated habitat disturbances to hydrologic regime and light availability that may occur naturally, or through active management practices aimed at ensuring the sustainability of L. melissifolia, and determined species responses to these changes. First year plants of L. melissifolia and B. ovata were grown at varying densities, received flooded or non-flooded treatments, and 100%, 47%, or 21% light availabilities. For both species, density effects in combination with light availability and flooding regime influenced total biomass accumulation. In response to flooding treatments, B. ovata exhibited a high degree of plasticity in biomass allocated between above- and belowground tissues, whereas biomass allocation in L. melissifolia was relatively unaffected. Interspecific competition occurred primarily in non-flooding treatments. Our study highlighted the complexity of the relationship of L. melissifolia and B. ovata functional trait responses to changes in abiotic and biotic factors, and indicated that it will be necessary to consider entire plant community response to mitigate increased competitive interactions and ensure survival of L. melissifolia populations.The accepted manuscript in pdf format is listed with the files at the bottom of this page. The presentation of the authors' names and (or) special characters in the title of the manuscript may differ slightly between what is listed on this page and what is listed in the pdf file of the accepted manuscript; that in the pdf file of the accepted manuscript is what was submitted by the author