Easy Ambient Sonic-spray Ionization Mass Spectrometry Research Articles

Rapid and direct detection of artificially aged papers employing easy ambient sonic-spray ionization mass spectrometry.

The effort to make fake documents look real leads to the use of crickets and beverages to produce artificially aged papers, as land titles, based on yellowing caused by the use of these methods. An old practice in Brazil, called "cricketing", has led to the misappropriation of Brazilian land using these documents. We propose a rapid, simple, instantaneous and non-destructive method to identify artificially aged papers by easy ambient sonic-spray ionization mass spectrometry (EASI-MS) analysis. Three typical aging procedures were used to obtain artificially aged papers using coffee, cola drink, and crickets, with the papers being analyzed by EASI-MS. Multivariate statistical analyses were performed on the data to find the sample groups and to study the most relevant ions of each ageing procedure. High-resolution MS (HRMS) was used to obtain the exact masses and attribute formulae to relevant ions present in the samples. The combination of EASI-MS and multivariate statistical analyses allowed us to identify the most relevant ions to classify the adulteration of documents and HRMS identified most of these relevant ions. TMS fingerprinting in combination with multivariate analysis also demonstrated that this approach can qualitatively differentiate all the examined paper samples. We developed a cheap, fast and easy method that can help to elucidate counterfeit documents that have been artificially aged, helping to identify chemical additives and one that can be used in forensic laboratories.

Investigating the Uptake of Arsenate by Chlamydomonas reinhardtii Cells and its Effect on their Lipid Profile using Single Cell ICP-MS and Easy Ambient Sonic-Spray Ionization-MS.

The complementary use of single cell atomic mass spectrometry (MS) and ambient molecular MS allowed for the in-depth study of arsenate uptake by Chlamydomonas reinhardtii cells and of the effect this toxic metalloid species has on their lipid profile. Compared to conventional inductively coupled plasma mass spectrometry (ICP-MS) analysis, in which case hundreds of thousands of cells are digested and then analyzed, it is demonstrated that single cell (SC) ICP-MS provides uptake data that are potentially of greater biological relevance. This includes the arsenic mass distribution within the cell population, which fits to a log-normal probability function, the most frequently contained arsenic mass within the cells (1.5-1.8 fg As per cell), and the mean arsenic uptake value (ranging from 2.7 to 4.1 fg As per cell for the three arsenate incubation concentrations, that is, 15, 22.5, and 30 μg As per mL) derived from the log-normal arsenic mass distribution within the cell population. The SC approach also allows for differentiating the arsenic present in and/or adsorbed on the cells, from the arsenic present in the extracellular solution, in a single analysis. In a similar fashion, ambient molecular MS in the form of desorption easy ambient sonic spray ionization (EASI) -MS was used to rapidly profile cell membrane lipids from cells spotted directly on a glass slide. EASI-MS analysis revealed that cells grown in the presence of increasing concentrations of arsenate exhibited changes in the degree of saturation of their membrane lipids, as was observed by the increasing intensity ratio of lipids with less unsaturated acyl chains to the same type of lipids with more unsaturated fatty acid chains. Thus, indicating "homeoviscous adaptation" of extraplastidial and thylakoid cell membranes, induced by the presence of arsenate.

The impacts of the raising regime of Salmon species on their triacylglycerol composition revealed by easy ambient sonic-spray ionization mass spectrometry

Marine fish consumption is rising around the world due to the high quality of its nutritional components, including long chain polyunsaturated fatty acids (LC-PUFA), which are abundant and found as triacylglycerol (TAG) in the muscle and skin of Salmonidae family. Farm raised and wild species of Salmon have different diets, that directly influences their TAG composition. In this work, we demonstrate the evaluation of TAG composition of salmon species as an authenticity screening parameter. For this purpose, we propose the use of ambient mass spectrometry, here represented by the thermal imprinting (TI) easy ambient sonic-spray ionization mass spectrometry (EASI-MS), to offer a fast and ecofriendly method for TAG extraction and characterization of fish muscles and skins. Specifically, TI-EASI-MS was employed to obtain the TAG profiles of different species from Salmonids, which were compared using multivariate statistical analysis. Clear differentiation of wild-raised fishes was achieved based on their higher content of ions attributed to TAG containing PUFA when compared to farm-raised fishes. The TI extraction method was also compared to the standard Bligh & Dyer extraction protocol and the techniques were equivalent for Salmon species differentiation.

Ambient mass spectrometry in foodomics studies

The current and future potential role of ambient mass spectrometry (AMS) in the fields of recently created discipline of foodomics is discussed. The main focus was set on the literature published between 2014 and 2018, although a few earlier papers of special interest have been included. Several examples for the successful application of AMS techniques including direct analysis in real time (DART), desorption electrospray ionization (DESI), easy ambient sonic spray ionization mass spectrometry (EASI-MS) and paper spray mass spectrometry (PS-MS) are presented.

Direct Detection of Triacetone Triperoxide (TATP) in Real Banknotes from ATM Explosion by EASI‐MS

AbstractIn Brazil, automated teller machine (ATM) has become a major target of theft incursions toward explosion. Efficient analysis of explosives residues on suspect banknotes is a serious issue in forensic labs, and guide to the crime solution. Easy ambient sonic‐spray ionization mass spectrometry (EASI‐MS) is shown to be a simple and selective screening tool to identify peroxide explosives on real banknotes collected from ATM explosion. Analyses were carried out directly on the banknotes surfaces without any sample preparation, identifying triacetone triperoxide (TATP) and diacetone diperoxide (DADP). Homemade EASI source was coupled to ultrahigh‐resolution and ultrahigh accuracy FT‐ICR MS and revealed the ion of m/z 245 correspondent to sodiated TATP [C9H18O6Na]+ and the ion of m/z 171 related to sodiated DADP [C6H12O4Na]+, ions that is the sodiated DADP and the ions of m/z 173 and 189 related to [C6H14O4Na]+ and [C6H14O4K]+, respectively, which are associated to chemical markers of TATP domestic route synthesis. EASI source coupled to a single quadrupole mass spectrometer provides an intelligent and simple way to identify the explosives TATP, DADP and its domestic synthesis markers.

Incorporation of conjugated fatty acids into Nile tilapia (Oreochromis niloticus).

The aim of this work was to improve the nutritional quality of Nile tilapia meat through enriched diets with conjugated isomers of linolenic acid from tung oil. The transfer process of conjugated fatty acids (CFAs) into fish muscle tissue was evaluated by gas chromatography-flame ionization detection (GC-FID) and easy ambient sonic-spray ionization mass spectrometry (EASI-MS). The results showed that conjugated fatty acids were transferred from enriched diet for muscle tissue of Nile tilapia. Conjugated linoleic acids biosynthesis from conjugated linolenic acids was also observed after 10 days. Other important fatty acids such as docosahexaenoic (DHA), eicosapentaenoic (EPA) and arachidonic (AA) acids were also identified over time; however, DHA showed the highest concentration when compared with EPA and AA compounds. Therefore, the nutritional quality of Nile tilapia was improved through feeding with enriched diets. The ingestion of these fish may contribute to reaching adequate levels of daily CFA consumption. Furthermore, other important substances which play an important role in human metabolism, such as EPA, DHA and AA, can also be ingested together with CFA. © 2016 Society of Chemical Industry.

Easy ambient sonic-spray ionization mass spectrometry for tissue imaging

Easy ambient sonic-spray ionization mass spectrometry (EASI-MS) can be applied for tissue imaging when the application of high voltage is impractical or undesirable.

Food quality and authenticity screening via easy ambient sonic-spray ionization mass spectrometry.

This review is the first to summarize a decade of studies testing the use of easy ambient sonic-spray ionization mass spectrometry (EASI-MS) and its several sister techniques, Venturi (V-EASI), thermal imprinting (TI-EASI) and Spartan (S-EASI) mass spectrometry in food quality control and authentication. Since minimal or no sample preparation is required, such ambient desorption/ionization techniques have been shown to provide direct, fast and selective fingerprinting characterization at the molecular level based on the pools of the most typical components. They have also been found to be applicable on intact, undisturbed samples or on simple solvent extracts. Fundamentals of EASI-MS and its sister techniques, including mechanisms, devices, parameters and strategies, as well as the many applications reported for food analysis, are summarized and discussed.

Using the L/O ratio to determine blend composition in biodiesel by EASI-MS corroborated by GC-FID and GC-MS

Easy ambient sonic-spray ionization mass spectrometry (EASI-MS) is applied to the analysis of biodiesel blends prepared from soybean and animal fat biodiesel.

Analysis of sexual assault evidence: statistical classification of condoms by ambient mass spectrometry.

Desorption electrospray ionization mass spectrometry (DESI-MS) and easy ambient sonic-spray ionization mass spectrometry (EASI-MS) are employed here in the forensic analysis of chemical compounds found in condoms and relative traces, and their analytical performances are compared. Statistical analysis of data obtained from mass spectra only was applied in order to obtain classification rules for distinguishing ten types of condoms. In particular, two supervised chemometric techniques [linear discriminant analysis (LDA) and soft independent modeling of class analogy (SIMCA)] were carried out on absolute and relative intensity values to test the performances of statistical models in terms of predictive capacity. The achieved classification of samples was excellent because of the high prediction percentages of the method used both for DESI and EASI mass spectrometry analyses, confirming these two as potential ambient ionization techniques for forensic analyses in case of sexual assault crimes. EASI-MS showed 99% prediction ability for LDA using relative data and 100% prediction ability for SIMCA using both absolute and relative ones, while DESI showed 94% prediction ability for both LDA and SIMCA. The absence of any sample preparation technique gives advantages in terms of sample preservation and reduced contamination, allowing successive analyses to be performed on the same sample by other techniques.

Comprehensive characterization of lipids from Amazonian vegetable oils by mass spectrometry techniques

An integrative approach in mass spectrometry (MS) comprising gas chromatography coupled to MS (GC–MS), ultra-efficiency liquid chromatography coupled to MS (UPLC–MS) and easy ambient sonic-spray ionization MS (EASI-MS) is proposed for the comprehensive characterization of Amazonian oils. Coconut, andiroba and castor seed oils, which are vastly sold in markets of the Amazonian region of Brazil, were selected as a representative test set. These oils were found to contain several lipids such as triacylglycerides (TAGs), fatty acids (FAs), phytosterols and limonoids. In the analyzed samples 30 different TAGs, 11 FAs, 6 phytosterols and 7 limonoids were identified. The antioxidant capacity (AOC) of the oils, as measured by their oxygen radical absorbance capacity (ORAC), was also used to evaluate their potential biological properties as well as their possible consumption as food. Edible virgin coconut oil was the most active (0.720±0.001 Trolox eq./mmol), whereas considerable lower activity was observed for andiroba and castor seed oils. The antimicrobial activities of the oils were also recorded against a panel of pathogenic bacteria and fungi in which andiroba oil was the only one that was active, solely against Enterococcus aeruginosa.

Study on variation of lipids during different growth phases of living cyanobacteria using easy ambient sonic-spray ionization mass spectrometry.

Lipids are important components of cell membranes and thylakoids in cyanobacteria, and they play vital roles in various biological activities. Real-time tracing of the variation of membrane lipids can provide insights of the physiological status of cyanobacterial cells. In this work, easy ambient sonic-spray ionization mass spectrometry (EASI-MS) was utilized to investigate the changes of acidic lipids in unicellular (Synechocystis 6803, Synechococcus 7002) and filamentous (Anabaena 7120) cyanobacteria during different growth phases. A sqdX mutant with a reduced synthesis of sulfoquinovosyl diacylglycerol (SQDG) was constructed to verify the acquired data of EASI-MS. Principal component analysis (PCA) was performed to compare the acquired data, enabling the discrimination of different species of cyanobacteria in day-to-day analysis. The results showed that the three representative cyanobacteria and their growth status can be easily determined on the basis of the lipids components detected by EASI-MS. Very interestingly, significant decreases of the ratios of SQDG/PG and dramatic changes of the unsaturation level of lipids were observed in different culture times in these cyanobacteria, and these two unique characters can be used describe the aging of cyanobacteria.

Ambient sonic‐spray ionization mass spectrometry for rapid monitoring of secondary oxidation products in biodiesel

This paper proposes the use of easy ambient sonic‐spray ionization mass spectrometry (EASI‐MS) to detect markers of high‐level oxidation in biodiesel via a simple and rapid single‐shot analytical protocol. Soybean biodiesel was oxidized in Rancimat and then analyzed at different time periods by both EASI‐MS and traditional physicochemical methods. Major changes in the EASI(+)‐MS profile as well in the peroxide value, acidity, and kinematic viscosity were observed after the induction period (IP). Fatty acid methyl esters (FAME) and their respective hydroperoxides were primarily identified using EASI‐MS in fresh biodiesel and at the initial stages of oxidation. After the IP, EASI‐MS revealed the formation of dimers and low‐mass non‐volatile molecules, such as aldehydes, due to hydroperoxide breakdown. Both the dimers and aldehydes are attributed to secondary oxidation products. Therefore, EASI‐MS was found to provide a fast, direct, and accurate technique to identify markers in biodiesel with high‐level of oxidation.Practical applications: EASI‐MS is a useful technique to identify primary and secondary oxidation products formed in biodiesel in a single procedure that is rapid and does not require sample preparation. Therefore, EASI‐MS has potential applications in biodiesel routine analysis to screen samples with high‐levels of oxidation.EASI‐MS provides a fast, direct, and accurate technique to identify markers in biodiesel with high‐level of oxidation.

Unsaturation levels in biodiesel via easy ambient sonic-spray ionization mass spectrometry

Using a non-natural fatty acid methyl ester (FAME) as an internal standard we evaluated the ability of easy ambient sonic-spray ionization mass spectrometry (EASI-MS) to quantitate the unsaturated FAME levels in B100 biodiesel from soybean, canola and Jatropha curcas. The ability of EASI(+)-MS to discriminate between saturated versus unsaturated FAME was also evaluated. Calibration curves for the major FAME, those from linolenic, linoleic and oleic acids, showed good linearity with coefficient correlation >0.99 with the EASI(+)-MS method. The spike recoveries ranged from 76% to 127% with good repeatability and reproducibility as indicated by the relative standard deviation (RSD), which ranged from 5.1% to 17.7%. The accuracy of the method was established using a standard reference material (SRM). Real biodiesel samples were also quantitated via EASI(+)-MS, and the unsaturated FAME content was found to correlate adequately with the data obtained from the iodine number. Therefore, EASI(+)-MS was shown to provide fast, direct, linear and accurate quantitation of the unsaturated FAME in biodiesel samples.

Integrative Approach Using GC-MS and Easy Ambient Sonic-Spray Ionization Mass Spectrometry (EASI-MS) for Comprehensive Lipid Characterization of Buriti (Mauritia flexuosa) Oil

Buriti (Mauritia flexuosa L. f.) is a palm widely distributed in the Amazon Rain Forest of Brazil. Oil is extracted from buriti fruit and popularly used as a food resource and for medicinal purposes. Herein we report the use of an integrative approach based on mass spectrometry (MS) techniques comprising gas chromatography coupled to electron ionization mass spectrometry (GC-MS) and easy ambient sonic-spray ionization mass spectrometry (EASI-MS) with the objective to provide comprehensive lipid characterization of buriti oil. GC-MS analysis revealed the presence of many fatty acids (oleic, palmitic and linoleic), sterols beyond α- and β-tocopherol in buriti oil. EASI-MS allowed the characterization of fatty acids and many triaclyglycerides (TAG) in the negative and positive ion mode, respectively. Additionally, the antioxidant capacity (AC) was measured by the oxygen radical absorbance capacity assay (ORAC); this test was carried with the lipophilic and hydrophilic fractions of the buriti oil. Results revealed a lypophilic antioxidant capacity (LAC) of 1.8 ± 0.01 and hydrophilic antioxidant capacity (HAC) of 8.3 ± 0.01 μmol Trolox equivalents (TE) g−1 indicating that the buriti oil comprises a reliable source of antioxidant compounds that can be more explored for food purposes.

Evaluation of the fatty matter contained in microcapsules obtained by double emulsification and subsequent enzymatic gelation method

The objective of this study was to evaluate encapsulated fatty matter using double emulsification and subsequent enzymatic gelation method using soy protein isolate cross-linked by transglutaminase. For this purpose, six extractions methods (acids, alkaline and enzymatic methods) were used. The extraction methods showed differences, total or partial extraction being observed when using the acid method, alkaline enzymatic method and the acid method with direct determination of the fatty acid composition. The presence of triglycerides and ethyl ester was investigated in the microcapsules by easy ambient sonic-spray ionization mass spectrometry (EASI-MS), high performance size exclusion chromatography (HPSEC) and the fatty acid composition as determined by gas chromatography (GC). The microcapsules were shown to contain 1.07g omega-3 fatty acids / 100g microcapsules.

Quantitation of triacylglycerols in vegetable oils and fats by easy ambient sonic-spray ionization mass spectrometry

This innovative mass spectrometric technique provides simple, quick, and reliable quantitative analysis of triacylglycerols in vegetable oils and fats. The easy ambient sonic-spray ionization mass spectrometry (EASI-MS) technique provides simple, quick, and reliable qualitative analysis of triacylglycerols (TAG) in vegetable oils. The use of this ambient mass spectrometry technique, which does not require separation or derivatization before analysis, for precise quantitative analyses has yet to be demonstrated. In this study, the TAG composition of edible vegetable oils, hydrogenated vegetable oils and cocoa butter was quantitated by EASI-MS. The results were compared with those obtained by theoretical predictions of the TAG composition performed by a software projection, which uses a mathematical algorithm of distribution of the fatty acids (FA) in the TAG molecule, and by the direct gas chromatography method (GC-FID). Acceptable correlation coefficients were observed between the three methods during the analysis of vegetable oils and hydrogenated vegetable oils. EASI-MS offers not only simplicity, speed and selectivity for oil analysis but also precise quantitation of the TAG composition. Therefore, EASI-MS is a promising substitute for the more demanding and time-consuming standard protocols, which require separation and sometimes derivatization before analysis.

Brazil Nut Oil: Quality Control via Triacylglycerol Profiles Provided by Easy Ambient Sonic-Spray Ionization Mass Spectrometry

Brazil nut oil is one of the important Amazonian natural products in the global market. Despite its health benefits and applications in food and cosmetic industries, authentication and quality control of the oil are far from satisfactory. Several samples of Amazonian Brazil nut oil (authentic oils of different geographic origins, commercial oils, and oils adulterated with soybean oil) were evaluated by easy ambient sonic-spray ionization mass spectrometry (EASI-MS). The samples were characterized on the basis of triacylglycerol profiles, and their major ions were subjected to chemometric treatment (principal component analysis). The ambient mass spectrometry analysis and the set of major ions allowed the characterization of authentic oils, commercial oils, and adulterated oils (5% soybean oil) in a few minutes and without sample preparation. Therefore, it is shown that quality control of Amazonian vegetable oils can be readily accomplished by EASI-MS.

Direct characterization of commercial lecithins by easy ambient sonic-spray ionization mass spectrometry

Commercial lecithins are composed mainly of phospholipids and triacylglycerols. The analysis of the commercial lecithins, including their fraction of phospholipids, normally involves laborious and expensive protocols. Easy ambient sonic-spray ionization mass spectrometry (EASI-MS) is shown to be an efficient technique for the analysis of lipids. Samples of commercial lecithins including standards, refined, deoiled and modified soy lecithin were tested. Characteristic profiles of phosphatidylcholines and triacylglycerols are detected by EASI(+)-MS, whereas EASI(−)-MS provided phosphatidylethanolamines, glycophospholipids and free fatty acids profiles. Acetylated lecithins also displayed characteristic acetylated derivatives. EASI-MS data was also compared to MALDI-MS, and found to display richer compositional information. The industrial process applied to lecithin fabrication was also characterised via typical EASI-MS profiles. EASI-MS both in its positive and negative ion modes offers a direct, fast and efficient technique able to characterise commercial lecithin.

Triacylglycerols Oxidation in Oils and Fats Monitored by Easy Ambient Sonic‐Spray Ionization Mass Spectrometry

AbstractOxidation is the major cause of fat and oil deterioration which produces rancid and unpleasant flavors that drastically reduces their quality and nutritional value. The primary oxidation products are triacylglycerols (TAG) containing unsaturated fatty acyl hydroperoxides formed by a chain process occurring through free radical intermediates. The Rancimat method is currently the gold standard for measuring the oxidative stability of oils and fats. In this report, easy ambient sonic‐spray ionization mass spectrometry (EASI‐MS) is demonstrated to function as a direct (no pre‐separation or sample preparation steps), fast and accurate method to monitor oils and fats oxidation, providing detailed overviews of the most immediate TAG hydroperoxide products. The EASI‐MS results were compared to those obtained via the classical Rancimat test.