Papers by Raquel Cumeras
Ion Mobility Spectrometry (IMS) is an analytical technique based on ion separation in gaseous pha... more Ion Mobility Spectrometry (IMS) is an analytical technique based on ion separation in gaseous phase due to the di�erent ion mobility in an electric �eld. The IMS technology has fundamental advantages: high resolution (�ppb), fast measurements (�ms) and that ionization and characterization of the sample in IMS instruments occurs at ambient pressure [1]. E�orts for reducing size and cost while maintaining performances are being made by di�erent groups [2-3], and the work presented here is part of such approach, using micro- technologies for its implementation. These advantages make IMS a rapidly advancing technique with a wide spectrum of applications, including detection of narcotics, CW agents and explosives [2]. Experimentally had been see that the mobility K (cm2/V�s) of ions at constant temperature and pressure through a drift gas with density N (m-3), subject to an high electric �eld E (V/cm) doesn't remain constant, and that its dependence with the �led (E) can be expressed...
The modelling by numerical simulation of a Micro Ion Mobility Spectrometer developed for Security... more The modelling by numerical simulation of a Micro Ion Mobility Spectrometer developed for Security applications is pre-sented as a tool for designing a device system for sensing DMMP, TNT and ace-tone vapours. In IMS target ions are separated by the proper application of separation voltages to the electrodes of the system. By Modelling the optimum volt-ages have been obtained.
Exhaled breath not only contains oxygen, nitrogen and carbon dioxide but also volatile organic co... more Exhaled breath not only contains oxygen, nitrogen and carbon dioxide but also volatile organic compounds. Those are chemicals from inside and outside the body that evaporate at room temperature and are the source of most breath odors. Also contains a host of "confounders" inhaled from the ambient air—including molecules of pollution, paint, furniture, even carpet fibers—that can interfere with breath sampling. In fact, what people eat, what medications they take and how often they brush their teeth can all affect their breath signature. Breath analysis can be done with various forms of mass spectrometry, but there are also simpler methods for specific purposes, such as the Ion Mobility Spectrometry. Gastric interferences in exhaled breath in Ion Mobility Spectrometry chromatograms will be shown for different flavor sweets.
A micro Planar high-Field Asymmetric waveform Ion Mobility Spectrometer (P-FAIMS) has been simula... more A micro Planar high-Field Asymmetric waveform Ion Mobility Spectrometer (P-FAIMS) has been simulated in air at ambient pressure using COMSOL Multiphysics software. Targeted analytes used in simulations are vapor phase compounds for security applications. In P-FAIMS target ions are discriminated by the application of the proper separation voltages to the electrodes of the system. By modeling, optimum voltages for achieving the proper sensitivity have been obtained and dual detection is achieved for ions with opposite charges.
Differential mobility spectrometry (DMS) Field asymmetric ion mobility spectrometry (FAIMS) Huang... more Differential mobility spectrometry (DMS) Field asymmetric ion mobility spectrometry (FAIMS) Huanglongbing (HLB) Candidatus Liberibacter asiaticus (CLas) a b s t r a c t Volatile organic compounds (VOCs) are off-gassed from all living organisms and represent end products of metabolic pathways within the system. In agricultural systems, these VOCs can provide important information on plant health and can ordinarily be measured non-invasively without harvesting tissue from the plants. Previously we reported a portable gas chromatography/differential mobility spectro-metry (GC/DMS) system that could distinguish VOC profiles of pathogen-infected citrus from healthy trees before visual symptoms of disease were present. These measurements were taken directly from canopies in the field, but the sampling and analysis protocol did not readily transfer to a controlled greenhouse study where the ambient background air was saturated with volatiles contained in the facility. In this study, we describe for the first time a branch enclosure uniquely coupled with GC/DMS to isolate and measure plant volatiles. To test our system, we sought to replicate our field experiment within a contained greenhouse and distinguish the VOC profiles of healthy versus citrus infected with Candidatus Liberibacter asiaticus. We indeed confirm the ability to track infection-related trace biogenic VOCs using our sampling system and method and we now show this difference in Lisbon lemons (Ci-trus×limon L. Burm. f.), a varietal not previously reported. Furthermore, the system differentiates the volatile profiles of Lisbon lemons from Washington navels [Citrus sinensis (L.) Osbeck] and also from Tango mandarins (Citrus reticulata Blanco). Based on this evidence, we believe this enclosure-GC/DMS system is adaptable to other volatile-based investigations of plant diseases in greenhouses or other contained settings, and this system may be helpful for basic science research studies of infection mechanisms .
Ion Mobility Spectrometry (IMS) is a widely used and ‘well-known’ technique of ion separation in ... more Ion Mobility Spectrometry (IMS) is a widely used and ‘well-known’ technique of ion separation in the gaseous phase based on the differences of ion mobilities under an electric field. This technique has received increased interest over the last several decades as evidenced by the pace and advances of new IMS devices available. In this review we explore the hyphenated techniques that are used with IMS, specifically mass spectrometry as an identification approach and a multi-capillary column as a preseparation approach. Also, we will pay special attention to the key figures of merit of the ion mobility spectrum and how data sets are treated, and the influences of the experimental parameters on both conventional drift time IMS (DTIMS) and miniaturized IMS also known as high Field Asymmetric IMS (FAIMS) in the planar configuration. The present review article is preceded by a companion review article which details the current instrumentation and contains the sections that configure both conventional DTIMS and FAIMS devices. These reviews will give the reader an insightful view of the main characteristics and aspects of the IMS technique.
Ion Mobility Spectrometry (IMS) is a widely used and ‘well-known’ technique of ion separation in ... more Ion Mobility Spectrometry (IMS) is a widely used and ‘well-known’ technique of ion separation in the gaseous phase based on the differences in ion mobilities under an electric field. All IMS instruments operate with an electric field that provides space separation, but some IMS instruments also operate with a drift gas flow that provides also a temporal separation. In this review we will summarize the current IMS instrumentation. IMS techniques have received an increased interest as new instrumentation and have become available to be coupled with mass spectrometry (MS). For each of the eight types of IMS instruments reviewed it is mentioned whether they can be hyphenated with MS and whether they are commercially available. Finally, out of the described devices, the six most-consolidated ones are compared. The current review article is followed by a companion review article which details the IMS hyphenated techniques (mainly gas chromatography and mass spectrometry) and the factors that make the data from an IMS device change as a function of device parameters and sampling conditions. These reviews will provide the reader with an insightful view of the main characteristics and aspects of the IMS technique.
We explored the feasibility of collecting exhaled breath from a moribund gray whale (Eschrichtius... more We explored the feasibility of collecting exhaled breath from a moribund gray whale (Eschrichtius robustus) for potential non-invasive health monitoring of marine mammals. Biogenic volatile organic compound (VOC) profiling is a relatively new field of research, in which the chemical composition of breath is used to non-invasively assess the health and physiological processes on-going within an animal or human. In this study, two telescopic sampling poles were designed and tested with the primary aim of collecting whale breath exhalations (WBEs). Once the WBEs were successfully collected, they were immediately transferred onto a stable matrix sorbent through a custom manifold system. A total of two large volume WBEs were successfully captured and pre-concentrated onto two Tenax ® -TA traps (one exhalation per trap). The samples were then returned to the laboratory where they were analyzed using solid phase micro extraction (SPME) and gas chromatography/mass spectrometry (GC/MS). A total of 70 chemicals were identified (58 positively identified) in the whale breath samples. These chemicals were also matched against a database of VOCs found in humans, and 44% of chemicals found in the
IntroductionThere are numerous analytical detection methods available for human breath investigat... more IntroductionThere are numerous analytical detection methods available for human breath investigations. The major spectrometric methods used are solid phase micro extraction-gas chromatography coupled to mass spectrometry (SPME-GC/ MS) [1–4], selected ion flow tube mass spectrometry (SIFT-MS) [5–9], proton transfer reaction mass spectrometry (PRT-MS) [10–14], and multi-capillary column coupled to ion mobility spectrometry (MCC/IMS) [15–20]. In all cases mentioned, a non–invasive and an easy method for early diagnosis or therapy monitoring are developed by identifying disease-specific biomarkers in the breath of patients.Ion Mobility Spectrometry (IMS) is an analytical technique to determine and discriminate analytes in the gas phase and has been used from the early 70’s, originally for military use and civil protection [21]. But until the 90’s this technique has not begun to develop considerably. Initially it was thought that the modern analytical ion mobility spectrometers would be mor ...
Multi-Capillary Column coupled to an Ion Mobility
Spectrometer (MCC/IMS) is widely used for Brea... more Multi-Capillary Column coupled to an Ion Mobility
Spectrometer (MCC/IMS) is widely used for Breath
Analysis. During this analysis a part of room air variations,
also operational background emissions have to be considered.
In the study reported here we analyze the background
emissions of two different intubation methods, an endotracheal
tube and a laryngeal mask used in anesthesia. Also a
straight connector used to collect the patients breath is
studied. Laboratory measurements have been carried out
with MCC/IMS and also with a Gas Chromatograph—Mass
Selective Detector (GC/MSD), showing different plastic compositions
and MCC/IMS chromatographs. Patients breath
measurements were carried out while the patients were anesthetized
and intubated. In the breath analysis of patients under
anesthesia one specific peak of the endotracheal tube has been
found, and also two specific peaks from the laryngeal mask.
Nonspecific peak due to the straight connector has also been
found, showing its suitability for sampling collection.
Journal of Mathematical Chemistry
A micro Planar high-Field Asymmetric waveform Ion Mobility Spectrometer (P-FAIMS) operating at am... more A micro Planar high-Field Asymmetric waveform Ion Mobility Spectrometer (P-FAIMS) operating at ambient pressure and temperature has been simulated using COMSOL Multiphysics software. P-FAIMS is based on ion gas-phase separation due to the dependence of ion mobility with electric field. Ions are selected by a DC voltage characteristic of each ion kind. Physics of ion behaviour in high electric fields conditions is well known but not the chemistry behind ion reactions and kinetics. The aim of this work is the modelling of different kind of ions in a P-FAIMS having account of the main factors involved in their movement in the drift tube. Simulations of vapour phase ions of three compounds have been studied for different values of drift electric field amplitude to gas number density (E/N) ratio: protonated water clusters H+(H2O)n and \({{\rm O}_{2}^{-}({\rm H}_{2}{\rm O})_{n}}\) ions obtained in air, and a chemical warfare agent simulant DMMPH+ that emulates gas sarin. Ions were selected due to simulation needs of experimental data of the main quantities involved in the definition of ions mobilities. Results show that simulations of ions behaviour in a P-FAIMS are possible with COMSOL Multiphysics software and that the time and intensity at which ions are detected are in good agreement with experimental data from literature.
Sensors and Actuators B-chemical
A miniaturized Planar Field Asymmetric Ion Mobility Spectrometer (P-FAIMS) has been simulated in ... more A miniaturized Planar Field Asymmetric Ion Mobility Spectrometer (P-FAIMS) has been simulated in N2 at ambient pressure using COMSOL Multiphysics software. Micro-IMS is based on ion gas-phase separation due to the dependence of ion mobility with electric field. Ions are selected by a DC voltage characteristic of each kind of ion. The average kinetic behaviour of ions in high electric
Modeling of a Micro Ion Mobility Spectrometer (uIMS) is developed for sensing acetone (Ac) and di... more Modeling of a Micro Ion Mobility Spectrometer (uIMS) is developed for sensing acetone (Ac) and dimethyl methylphosphonate (DMMP) for Security Applications. In uIMS target ions are discriminated by the application of the proper separatio voltages to the electrodes of the system. Ions are modeled using literature values for their main parameters: K0, a2 and a4. By modeling, optimum voltages for achieving the proper sensitivity have been obtained.
Conference Presentations by Raquel Cumeras
The porosity of the outer poultry eggs shell allows pathogens to arrive inside egg by penetrating... more The porosity of the outer poultry eggs shell allows pathogens to arrive inside egg by penetrating the eggshell. Under
humid ambient storing conditions in refrigerators, eggs can be colonized by fungi and bacteria. Volatile organic
compounds (VOCs) are produced by bacteria and fungi as they proliferate, and these chemicals are emitted back
through the eggshell into the environment. Some of these compounds have low molecular weight and high volatility,
and almost 200 VOCs have been previously identified from contaminated eggs. In this work, we present the study of
metabolites from fungi inside hen eggs and their correlation with the fungi species-specific VOCs. Fresh-eggs(n=2)
and 2months old-eggs(n=4) were stored under normal ambient humid conditions, and they were analyzed using noninvasive
techniques: Solid Phase Microextraction Headspace Gas Chromatography Mass Spectrometry(SPME-HSGC/
MS) and Headspace Gas Chromatography Differential Mobility Spectrometry(HS-GC/DMS). Eggs were placed
inside vials (neck-size-70mm,PTFE-cap,capacity-240ml) that were previously cleaned in a vacuum-oven(160ºC,3h),
and samples were taken after flushing the vials with dryUHP air for 2min. Upon experimetns completion, all eggs
were opened to check fungus presence and identification. DNA was extracted from mycelia of fungal cultures on
APDA, and bacterial colonies that were grown on KB medium. PCR products were sequenced and the fungi and
bacteria were identified using NCBI BLAST results. Petri dishes with grown fungi from eggs were analyzed with
SPME-GC/MS for metabolite confirmation. Almost 100 VOCs have been identified with GC/MS and are classified in
5-groups: fungi (present only in the eggs containing fungi); old (present only in the old eggs that may or may not
contain the fungi); healthy (present only in the eggs not containing the fungi); fresh (present only in the fresh eggs)
and all eggs (present in all eggs). Specific compounds that have been previously attributed to the identified fungi
(Botrytis cinerea and Cladosporium macrocarpum) have been matched with the identified compounds from the fungiinfected
eggs as well as from the analyzed colonies that were grown in vitro in petri-dishes. GC/MS results allow for
clear differentiation between non-infected eggs and eggs infected with fungi. Similarly to GC/MS results,
approximately 100 VOCs that are present in the eggs and absent in the vials with dry air blanks have been identified
in positive ion mode with GC/DMS. Additionally, 4 VOCs have been identified in the negative ion mode. The
advantage of GC/DMS is that it can detect both positive and negative ions in a single measurement, while only one
ion mode could be used at a time in some mass spectrometers . Although chemical identification with GC/DMS
sensor may be not straightforward or not possible, the sensor can be useful as a VOC monitoring tool in production
processes. Visual inspection of tested eggs revealed differences between non-infected eggs and eggs infected with
fungi. Non-invasive sampling of eggs pathogens. GC/DMS chemical signatures to be potentially used in production
process.
RATIONALE: Pressure ulcers are a major economic and clinical problem in hospitals and intensive c... more RATIONALE: Pressure ulcers are a major economic and clinical problem in hospitals and intensive care units. Current methods to detect and grade pressure ulcers use subjective measures, and, presently, there are few ways to detect developing pressure ulcers which are not clinically evident. Here we aimed to employ a model to identify if volatile organic compounds (VOCs) released from skin could Leporidae be used to biochemically separate intact skin from skin with experimentally-induced ulcers. METHODS: Four New Zealand female white rabbits underwent experimental ulcer formation on their right ear while their left ear was used as a control. Ulcers were created using 7/16 x 1/16-inch neodymium magnets (KJ Magnetic Inc, Pipersvile, PA) for 60 minutes. The goal was to achieve an erythematous ring without causing skin breakage or necrosis (i.e., an early-stage ulcer). Following ulcer formation, 5-mm diameter circular polydimethylsiloxane sorbent patches (PDMS; 0.6-mm thick, Goodfellow, Coraopolis, PA) were placed in close proximity to the ulcer on the experimental ears and in a similar location on the control ears. These were covered with polytetrafluoroethylene patches and affixed with Tegaderm® dressings. Skin VOCs were sampled with the PDMS for 30 minutes, and patches were removed, placed into sterile, nitrogen-purged borosolicate vials, capped, and routed for gas chromatography-mass spectrometry (GC/MS) analysis. For analysis, the sampled chemicals were desorbed off the patch at 200C, and 500 µL of headspace was aspirated from the vials and injected into a GC/MS instrument. Two rabbits underwent necropsy for ear histology. Data from each group was compared using Student's test for each VOC. t RESULTS: A significant number of emitted VOCs that were clearly different for the background were detected for each category of samples (ulcer vs non-ulcer). We identified two compounds which were unique to the ulcer group, one of which we tentatively identified as benzyl alcohol. A number of compounds were found to differ in abundance between ulcer and non-ulcer samples. Histologic analysis of two rabbits showed 1-1.5 cm erythematous lesions with acute heterophilic dermatitis, edema, and micro-hemorrhage on the ulcerated ears with normal findings on the control ears. CONCLUSIONS: In this small animal model study, we showed that VOCs are released from rabbit skin, VOCs change as a result of induced experimental ulcers, and VOCs likely correlate with histologic evidence of early-stage ulcers. VOCs may be useful for future, non-invasive monitoring of pressure ulcers in humans.
Solid-State Sensors, Actuators and Microsystems (TRANSDUCERS & EUROSENSORS XXVII), 2013 Transducers & Eurosensors XXVII: The 17th International Conference on
Aerosol Assisted Chemical Vapor Deposition (AACVD) induced via localized heating microsensor plat... more Aerosol Assisted Chemical Vapor Deposition (AACVD) induced via localized heating microsensor platforms is used to directly deposit tungsten oxide nanostructures from tungsten hexacarbonyl [W(CO)6] precursor. Results demonstrate the viability to grow and confine either nanoparticle-like or quasi-one-dimensional-like structures on microsensor devices by using the self-heating capability of the sensor platforms. The microsensors fabricated using this method show appreciable responses to toluene, with sensors based on films composed of nanoneedles and nanotubes having almost two-fold higher responses than sensors based on films composed of nanoparticles.
9th Spanish Conference on Electron Devices (CDE 13)
The needs of the Agrofood sector in terms of fast and low cost analytical devices and systems and... more The needs of the Agrofood sector in terms of fast and low cost analytical devices and systems and the capabilities of the Micro and Nano Technologies are reviewed and main R&D activity carried out in the last years is referenced. Despite the Food sector is very conservative in terms of introducing new technologies in their standard analysis procedures, it is expected that in the near future, sensors and Micro and Nano technologies can play an important role in commercial products.
Mobility Spectrometer (P-FAIMS) is developed for sensing explosives: DNT and TNB for security app... more Mobility Spectrometer (P-FAIMS) is developed for sensing explosives: DNT and TNB for security application. In P-FAIMS ions are discriminated by the application of the proper separation voltages to the electrodes of the system. Using FEM Multiphysics software, optimum voltages for achieving a correct separation of ionized molecules have been obtained for the studied compounds.
8th International Conference on Advanced Semiconductor Devices and Microsystems (ASDAM 2010)
Simulations of a planar micro Ion Mobility Spectrometer (μIMS) for sensing DMMP and Acetone vapou... more Simulations of a planar micro Ion Mobility Spectrometer (μIMS) for sensing DMMP and Acetone vapours for security applications are performed. In μIMS ions are discriminated by the application of the proper separation voltages to the electrodes of the system. By simulation, optimum voltages for achieving the proper sensitivity have been obtained.
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Papers by Raquel Cumeras
Spectrometer (MCC/IMS) is widely used for Breath
Analysis. During this analysis a part of room air variations,
also operational background emissions have to be considered.
In the study reported here we analyze the background
emissions of two different intubation methods, an endotracheal
tube and a laryngeal mask used in anesthesia. Also a
straight connector used to collect the patients breath is
studied. Laboratory measurements have been carried out
with MCC/IMS and also with a Gas Chromatograph—Mass
Selective Detector (GC/MSD), showing different plastic compositions
and MCC/IMS chromatographs. Patients breath
measurements were carried out while the patients were anesthetized
and intubated. In the breath analysis of patients under
anesthesia one specific peak of the endotracheal tube has been
found, and also two specific peaks from the laryngeal mask.
Nonspecific peak due to the straight connector has also been
found, showing its suitability for sampling collection.
Conference Presentations by Raquel Cumeras
humid ambient storing conditions in refrigerators, eggs can be colonized by fungi and bacteria. Volatile organic
compounds (VOCs) are produced by bacteria and fungi as they proliferate, and these chemicals are emitted back
through the eggshell into the environment. Some of these compounds have low molecular weight and high volatility,
and almost 200 VOCs have been previously identified from contaminated eggs. In this work, we present the study of
metabolites from fungi inside hen eggs and their correlation with the fungi species-specific VOCs. Fresh-eggs(n=2)
and 2months old-eggs(n=4) were stored under normal ambient humid conditions, and they were analyzed using noninvasive
techniques: Solid Phase Microextraction Headspace Gas Chromatography Mass Spectrometry(SPME-HSGC/
MS) and Headspace Gas Chromatography Differential Mobility Spectrometry(HS-GC/DMS). Eggs were placed
inside vials (neck-size-70mm,PTFE-cap,capacity-240ml) that were previously cleaned in a vacuum-oven(160ºC,3h),
and samples were taken after flushing the vials with dryUHP air for 2min. Upon experimetns completion, all eggs
were opened to check fungus presence and identification. DNA was extracted from mycelia of fungal cultures on
APDA, and bacterial colonies that were grown on KB medium. PCR products were sequenced and the fungi and
bacteria were identified using NCBI BLAST results. Petri dishes with grown fungi from eggs were analyzed with
SPME-GC/MS for metabolite confirmation. Almost 100 VOCs have been identified with GC/MS and are classified in
5-groups: fungi (present only in the eggs containing fungi); old (present only in the old eggs that may or may not
contain the fungi); healthy (present only in the eggs not containing the fungi); fresh (present only in the fresh eggs)
and all eggs (present in all eggs). Specific compounds that have been previously attributed to the identified fungi
(Botrytis cinerea and Cladosporium macrocarpum) have been matched with the identified compounds from the fungiinfected
eggs as well as from the analyzed colonies that were grown in vitro in petri-dishes. GC/MS results allow for
clear differentiation between non-infected eggs and eggs infected with fungi. Similarly to GC/MS results,
approximately 100 VOCs that are present in the eggs and absent in the vials with dry air blanks have been identified
in positive ion mode with GC/DMS. Additionally, 4 VOCs have been identified in the negative ion mode. The
advantage of GC/DMS is that it can detect both positive and negative ions in a single measurement, while only one
ion mode could be used at a time in some mass spectrometers . Although chemical identification with GC/DMS
sensor may be not straightforward or not possible, the sensor can be useful as a VOC monitoring tool in production
processes. Visual inspection of tested eggs revealed differences between non-infected eggs and eggs infected with
fungi. Non-invasive sampling of eggs pathogens. GC/DMS chemical signatures to be potentially used in production
process.
Spectrometer (MCC/IMS) is widely used for Breath
Analysis. During this analysis a part of room air variations,
also operational background emissions have to be considered.
In the study reported here we analyze the background
emissions of two different intubation methods, an endotracheal
tube and a laryngeal mask used in anesthesia. Also a
straight connector used to collect the patients breath is
studied. Laboratory measurements have been carried out
with MCC/IMS and also with a Gas Chromatograph—Mass
Selective Detector (GC/MSD), showing different plastic compositions
and MCC/IMS chromatographs. Patients breath
measurements were carried out while the patients were anesthetized
and intubated. In the breath analysis of patients under
anesthesia one specific peak of the endotracheal tube has been
found, and also two specific peaks from the laryngeal mask.
Nonspecific peak due to the straight connector has also been
found, showing its suitability for sampling collection.
humid ambient storing conditions in refrigerators, eggs can be colonized by fungi and bacteria. Volatile organic
compounds (VOCs) are produced by bacteria and fungi as they proliferate, and these chemicals are emitted back
through the eggshell into the environment. Some of these compounds have low molecular weight and high volatility,
and almost 200 VOCs have been previously identified from contaminated eggs. In this work, we present the study of
metabolites from fungi inside hen eggs and their correlation with the fungi species-specific VOCs. Fresh-eggs(n=2)
and 2months old-eggs(n=4) were stored under normal ambient humid conditions, and they were analyzed using noninvasive
techniques: Solid Phase Microextraction Headspace Gas Chromatography Mass Spectrometry(SPME-HSGC/
MS) and Headspace Gas Chromatography Differential Mobility Spectrometry(HS-GC/DMS). Eggs were placed
inside vials (neck-size-70mm,PTFE-cap,capacity-240ml) that were previously cleaned in a vacuum-oven(160ºC,3h),
and samples were taken after flushing the vials with dryUHP air for 2min. Upon experimetns completion, all eggs
were opened to check fungus presence and identification. DNA was extracted from mycelia of fungal cultures on
APDA, and bacterial colonies that were grown on KB medium. PCR products were sequenced and the fungi and
bacteria were identified using NCBI BLAST results. Petri dishes with grown fungi from eggs were analyzed with
SPME-GC/MS for metabolite confirmation. Almost 100 VOCs have been identified with GC/MS and are classified in
5-groups: fungi (present only in the eggs containing fungi); old (present only in the old eggs that may or may not
contain the fungi); healthy (present only in the eggs not containing the fungi); fresh (present only in the fresh eggs)
and all eggs (present in all eggs). Specific compounds that have been previously attributed to the identified fungi
(Botrytis cinerea and Cladosporium macrocarpum) have been matched with the identified compounds from the fungiinfected
eggs as well as from the analyzed colonies that were grown in vitro in petri-dishes. GC/MS results allow for
clear differentiation between non-infected eggs and eggs infected with fungi. Similarly to GC/MS results,
approximately 100 VOCs that are present in the eggs and absent in the vials with dry air blanks have been identified
in positive ion mode with GC/DMS. Additionally, 4 VOCs have been identified in the negative ion mode. The
advantage of GC/DMS is that it can detect both positive and negative ions in a single measurement, while only one
ion mode could be used at a time in some mass spectrometers . Although chemical identification with GC/DMS
sensor may be not straightforward or not possible, the sensor can be useful as a VOC monitoring tool in production
processes. Visual inspection of tested eggs revealed differences between non-infected eggs and eggs infected with
fungi. Non-invasive sampling of eggs pathogens. GC/DMS chemical signatures to be potentially used in production
process.