Characterization of Biodegraded Ignitable Liquids by Headspace–Ion Mobility Spectrometry

The detection of ignitable liquids (ILs) can be crucial when it comes to determining arson cases. Such identification of ILs is a challenging task that may be affected by a number of factors. Microbial degradation is considered one of three major processes that can alter the composition of IL residues. Since biodegradation is a time related phenomenon, it should be studied at different stages of development. This article presents a method based on ion mobility spectroscopy (IMS) which has been used as an electronic nose. In particular, ion mobility sum spectrum (IMSS) in combination with chemometric techniques (hierarchical cluster analysis (HCA) and linear discriminant analysis (LDA)) has been applied for the characterization of different biodegraded ILs. This method intends to use IMSS to identify a range of ILs regardless of their degree of biodegradation. Three ILs (diesel, gasoline and kerosene) from three different commercial brands were evaluated after remaining in a soil substrate for several lengths of time (0, 2, 5, 13 and 38 days). The HCA results showed the samples’ trend to fall into categories characterized by ILs type and biodegradation time. The LDAs allowed a 99% successful classification of the samples according to the IL type. This is the first time that an HS-IMS technique has been used to detect ILs that have undergone biodegradation processes. The results show that IMS may be a promising alternative to the current standard method based on gas-chromatography for the analysis of biodegraded ILs. Furthermore, no pretreatment of the samples nor the use of a solvent is required.

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Novel method based on ion mobility spectrometry sum spectrum for the characterization of ignitable liquids in fire debris

Talanta ◽

10.1016/j.talanta.2019.02.063 ◽

2019 ◽

Vol 199 ◽

pp. 189-194 ◽

Cited By ~ 8

Author(s):

María José Aliaño-González ◽

Marta Ferreiro-González ◽

Gerardo F. Barbero ◽

Miguel Palma

Keyword(s):

Ion Mobility Spectrometry ◽

Ion Mobility ◽

Ignitable Liquids ◽

Fire Debris ◽

Novel Method ◽

In Fire

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Chemometric approach to quality characterization of milk-based kombucha beverages

Mljekarstvo ◽

10.15567/mljekarstvo.2021.0201 ◽

2021 ◽

Vol 71 (2) ◽

pp. 83-94

Author(s):

Jasmina Vitas ◽

Keyword(s):

Fatty Acids ◽

Milk Fat ◽

Unsaturated Fatty Acids ◽

Principal Component ◽

Unknown Origin ◽

Hierarchical Cluster ◽

Monounsaturated Fatty Acids ◽

Data Set ◽

Linear Discriminant

Milk-based kombucha beverages were obtained conducting kombucha lead fermentation of milk. In order to discriminate the analysed samples and to detect similarities or dissimilarities among them in the space of experimentally determined variables, hierarchical cluster analysis (HCA) and principal component analysis (PCA) were applied. Linear discriminant analysis (LDA) was conducted on the raw data set in order to find a rule for allocating a new sample of unknown origin to the correct group of samples. In the space of the variables analysed by HCA, the dominant discriminating factor for the studied samples of kombucha beverages is the milk fat (MF) content, followed by total unsaturated fatty acids content (TUFA), monounsaturated fatty acids content (MUFA) and polyunsaturated fatty acids content (PUFA). The samples with 0.8 and 1.6% milk fat belong to the same cluster in the space of the analysed variables due to similarities in their AADPPH. It was determined by LDA that there was the biggest difference in quality between the groups of products with winter savoury and stinging nettle, while the highest similarity is between groups of products with wild thyme and peppermint regarding their pH values and antioxidant activity expressed as AADPPH.

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Discrimination of Ignitable Liquid Residues in Burned Petroleum-Derived Substrates by Using HS-MS eNose and Chemometrics

Sensors ◽

10.3390/s21030801 ◽

2021 ◽

Vol 21 (3) ◽

pp. 801

Author(s):

Barbara Falatová ◽

Marta Ferreiro-González ◽

José Luis P. Calle ◽

José Ángel Álvarez ◽

Miguel Palma

Keyword(s):

Accurate Determination ◽

Hierarchical Cluster ◽

Mass Spectrometry Data ◽

Gas Chromatography Mass Spectrometry ◽

Linear Discriminant ◽

Synthetic Fibers ◽

Ignitable Liquids ◽

Fire Debris ◽

American Society ◽

Ignitable Liquid

Interpretation of data from fire debris is considered as one of the most challenging steps in fire investigation. Forensic analysts are tasked to identify the presence or absence of ignitable liquid residues (ILRs) which may indicate whether a fire was started deliberately. So far, data analysis is subjected to human interpretation following the American Society for Testing and Materials’ guidelines (ASTM E1618) based on gas chromatography–mass spectrometry data. However, different factors such as interfering pyrolysis compounds may hinder the interpretation of data. Some substrates release compounds that are in the range of common ignitable liquids, which interferes with accurate determination of ILRs. The aim of the current research is to investigate whether headspace–mass spectroscopy electronic nose (HS-MS eNose) combined with pattern recognition can be used to classify different ILRs from fire debris samples that contain a complex matrix (petroleum-based substrates or synthetic fibers carpet) that can strongly interfere with their identification. Six different substrates—four petroleum-derived substrates (vinyl, linoleum, polyester, and polyamide carpet), as well as two different materials for comparison purposes (cotton and cork) were used to investigate background interferences. Gasoline, diesel, ethanol, and charcoal starter with kerosene were used as ignitable liquids. In addition, fire debris samples were taken after different elapsed times. A total of 360 fire debris samples were analyzed. The obtained total ion mass spectrum was combined with unsupervised exploratory techniques such as hierarchical cluster analysis (HCA) as well as supervised linear discriminant analysis (LDA). The results from HCA show a strong tendency to group the samples according to the ILs and substrate used, and LDA allowed for a full identification and discrimination of every ILR regardless of the substrate.

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A Screening Method Based on Headspace-Ion Mobility Spectrometry to Identify Adulterated Honey

Sensors ◽

10.3390/s19071621 ◽

2019 ◽

Vol 19 (7) ◽

pp. 1621 ◽

Cited By ~ 8

Author(s):

María José Aliaño-González ◽

Marta Ferreiro-González ◽

Estrella Espada-Bellido ◽

Miguel Palma ◽

Gerardo F. Barbero

Keyword(s):

Ion Mobility Spectrometry ◽

Ion Mobility ◽

Screening Method ◽

Principal Component ◽

Hierarchical Cluster ◽

High Price ◽

Intermediate Precision ◽

Linear Discriminant ◽

High Fructose ◽

Novel Method

Nowadays, adulteration of honey is a frequent fraud that is sometimes motivated by the high price of this product in comparison with other sweeteners. Food adulteration is considered a deception to consumers that may have an important impact on people’s health. For this reason, it is important to develop fast, cheap, reliable and easy to use analytical methods for food control. In the present research, a novel method based on headspace-ion mobility spectrometry (HS-IMS) for the detection of adulterated honey by adding high fructose corn syrup (HFCS) has been developed. A Box–Behnken design combined with a response surface method have been used to optimize a procedure to detect adulterated honey. Intermediate precision and repeatability studies have been carried out and coefficients of variance of 4.90% and 4.27%, respectively, have been obtained. The developed method was then tested to detect adulterated honey. For that purpose, pure honey samples were adulterated with HFCS at different percentages (10–50%). Hierarchical cluster analysis (HCA) and principal component analysis (PCA) showed a tendency of the honey samples to be classified according to the level of adulteration. Nevertheless, a perfect classification was not achieved. On the contrary, a full classification (100%) of all the honey samples was performed by linear discriminant analysis (LDA). This is the first time the technique of HS-IMS has been applied for the determination of adulterated honey with HFCS in an automatic way.

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Isolation and Characterization of Salmonella Jumbo-Phage pSal-SNUABM-04

Viruses ◽

10.3390/v13010027 ◽

2020 ◽

Vol 13 (1) ◽

pp. 27

Author(s):

Jun Kwon ◽

Sang Guen Kim ◽

Hyoun Joong Kim ◽

Sib Sankar Giri ◽

Sang Wha Kim ◽

...

Keyword(s):

Morphological Traits ◽

Open Reading Frames ◽

Genome Comparison ◽

The Novel ◽

Promising Alternative ◽

Isolation And Characterization ◽

Global Issue ◽

Reading Frames ◽

Predicted Function

The increasing emergence of antimicrobial resistance has become a global issue. Therefore, many researchers have attempted to develop alternative antibiotics. One promising alternative is bacteriophage. In this study, we focused on a jumbo-phage infecting Salmonella isolated from exotic pet markets. Using a Salmonella strain isolated from reptiles as a host, we isolated and characterized the novel jumbo-bacteriophage pSal-SNUABM-04. This phage was investigated in terms of its morphology, host infectivity, growth and lysis kinetics, and genome. The phage was classified as Myoviridae based on its morphological traits and showed a comparatively wide host range. The lysis efficacy test showed that the phage can inhibit bacterial growth in the planktonic state. Genetic analysis revealed that the phage possesses a 239,626-base pair genome with 280 putative open reading frames, 76 of which have a predicted function and 195 of which have none. By genome comparison with other jumbo phages, the phage was designated as a novel member of Machinavirus composed of Erwnina phages.

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A Methodology Based on FT-IR Data Combined with Random Forest Model to Generate Spectralprints for the Characterization of High-Quality Vinegars

Foods ◽

10.3390/foods10061411 ◽

2021 ◽

Vol 10 (6) ◽

pp. 1411

Author(s):

José Luis P. Calle ◽

Marta Ferreiro-González ◽

Ana Ruiz-Rodríguez ◽

Gerardo F. Barbero ◽

José Á. Álvarez ◽

...

Keyword(s):

Random Forest ◽

Raw Materials ◽

Principal Component ◽

Hierarchical Cluster ◽

Raw Material ◽

Support Vector ◽

Protected Designation Of Origin ◽

Ft Ir

Sherry wine vinegar is a Spanish gourmet product under Protected Designation of Origin (PDO). Before a vinegar can be labeled as Sherry vinegar, the product must meet certain requirements as established by its PDO, which, in this case, means that it has been produced following the traditional solera and criadera ageing system. The quality of the vinegar is determined by many factors such as the raw material, the acetification process or the aging system. For this reason, mainly producers, but also consumers, would benefit from the employment of effective analytical tools that allow precisely determining the origin and quality of vinegar. In the present study, a total of 48 Sherry vinegar samples manufactured from three different starting wines (Palomino Fino, Moscatel, and Pedro Ximénez wine) were analyzed by Fourier-transform infrared (FT-IR) spectroscopy. The spectroscopic data were combined with unsupervised exploratory techniques such as hierarchical cluster analysis (HCA) and principal component analysis (PCA), as well as other nonparametric supervised techniques, namely, support vector machine (SVM) and random forest (RF), for the characterization of the samples. The HCA and PCA results present a clear grouping trend of the vinegar samples according to their raw materials. SVM in combination with leave-one-out cross-validation (LOOCV) successfully classified 100% of the samples, according to the type of wine used for their production. The RF method allowed selecting the most important variables to develop the characteristic fingerprint (“spectralprint”) of the vinegar samples according to their starting wine. Furthermore, the RF model reached 100% accuracy for both LOOCV and out-of-bag (OOB) sets.

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Ion Mobility–Mass Spectrometry for Bioanalysis

Separations ◽

10.3390/separations8030033 ◽

2021 ◽

Vol 8 (3) ◽

pp. 33

Author(s):

Xavier Garcia ◽

Maria del Mar Sabaté ◽

Jorge Aubets ◽

Josep Maria Jansat ◽

Sonia Sentellas

Keyword(s):

Mass Spectrometry ◽

Liquid Chromatography ◽

Ion Mobility Spectrometry ◽

Ion Mobility ◽

Biological Samples ◽

Ion Mobility Mass Spectrometry ◽

Exogenous Compounds ◽

Analytical Separation

This paper aims to cover the main strategies based on ion mobility spectrometry (IMS) for the analysis of biological samples. The determination of endogenous and exogenous compounds in such samples is important for the understanding of the health status of individuals. For this reason, the development of new approaches that can be complementary to the ones already established (mainly based on liquid chromatography coupled to mass spectrometry) is welcomed. In this regard, ion mobility spectrometry has appeared in the analytical scenario as a powerful technique for the separation and characterization of compounds based on their mobility. IMS has been used in several areas taking advantage of its orthogonality with other analytical separation techniques, such as liquid chromatography, gas chromatography, capillary electrophoresis, or supercritical fluid chromatography. Bioanalysis is not one of the areas where IMS has been more extensively applied. However, over the last years, the interest in using this approach for the analysis of biological samples has clearly increased. This paper introduces the reader to the principles controlling the separation in IMS and reviews recent applications using this technique in the field of bioanalysis.

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In vivo optical endomicroscopy: two decades of translational research towards next generation diagnosis of eosinophilic esophagitis

Translational Medicine Communications ◽

10.1186/s41231-020-00080-z ◽

2021 ◽

Vol 6 (1) ◽

Author(s):

Andreas Wartak ◽

John G. Garber ◽

Qian Yuan ◽

Wayne G. Shreffler ◽

Paul E. Hesterberg ◽

...

Keyword(s):

Eosinophilic Esophagitis ◽

Massachusetts General Hospital ◽

Standard Of Care ◽

Depth Information ◽

Current Standard ◽

Promising Alternative ◽

White Light Endoscopy ◽

Related Risk ◽

Histopathologic Analysis

AbstractHistopathologic analysis of biopsy specimens obtained via white light endoscopy (WLE) is the gold standard for the diagnosis of several mucosal diseases in the upper gastrointestinal (GI) tract. However, this standard of care entails a series of critical shortcomings such as missing depth information, high costs, time inefficiency, low-resolution imaging in vivo, high sampling variability, missing intrinsic tissue-specific contrast, and anesthesia related risk. In the quest for a diagnostic technology to replace the current standard of care, in vivo optical endomicroscopy has emerged as a promising alternative. This paper tells the story of a cluster of optical microscopy-based modalities invented, further developed, or first-validated in the laboratory of Dr. Guillermo J. Tearney (Tearney Lab) at the Wellman Center for Photomedicine of Massachusetts General Hospital over the past two decades, that combined lead to a novel method for diagnosis of eosinophilic esophagitis (EoE). Rather than being a comprehensive literature review, this paper aims to describe the translational journey towards a disease specific diagnostic and research tool for this increasingly recognized yet poorly understood immune-mediated disorder of the esophagus.

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A Novel Processing Route for the Fabrication of Monolithic and Composite Silicon Nitride

MRS Proceedings ◽

10.1557/proc-287-309 ◽

1992 ◽

Vol 287 ◽

Author(s):

R. V. Raman ◽

S. V. Rele

Keyword(s):

Volume Fraction ◽

Hot Isostatic Pressing ◽

Thermal Exposure ◽

Processing Route ◽

Promising Alternative ◽

Α Phase ◽

Key Issues ◽

Novel Processing ◽

Composite Silicon

ABSTRACTCurrent hot isostatic consolidation methodology used for the fabrication of complex-shaped Si3N4-based components requires the use of an expensive glass encapsulation technique and extended thermal exposure (in hours) of the specimen. An alternative consolidation approach involving the use of solid pressure transmitting media under high pressure, has enabled the consolidation of Si3N4 alloys without the need for glass encapsulation.Characterization of microstructures and mechanical properties of this (MOR, fracture toughness) material has been carried out and will be presented. It has been noted that in Si 3N4/8%Y2O3-4%Al2O3 composition, consolidated using this approach, a significantly larger volume fraction of α phase has been retained compared with typically observed conversion in α⇒ β in hot isostatically pressed material or sintered material.Key issues for addressing densification and microstructure control using this process are presented. This rapid consolidation approach appears to be a promising alternative to hot isostatic pressing for the fabrication of complex-shaped Si3N4 components.

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