Capillary electrophoresis tandem mass spectrometry to determine multiclass cyanotoxins in reservoir water and spinach samples

Este estudio fue financiado por el Proyecto de Investigación PID2021-1278040B-I00 del MCIN/AEI /10.13039/501100011033 y “FEDER Una forma de hacer Europa”, y por el proyecto PROYEXCEL_00195 financiado por la Consejería de Universidad, Investigación e Innovación, Junta de Andalucía. RCM agradece al contrato predoctoral del Proyecto PID2021-1278040B-I00. Financiación para publicación en acceso abierto a cargo de Universidad de Granada / CBUA.Cyanotoxins constitute a group of toxic secondary metabolites, the presence of which in any water body poses a major health risk. Moreover, advanced organisms such as edible plants exposed to these toxins, are a possible pathway for human exposure. Green analytical chemistry is demanding environmentally friendly analytical techniques. In this sense, we propose the use of capillary electrophoresis coupled to tandem mass spectrometry (CE-MS/MS) to determine a mixture of eight cyanotoxins belonging to three different classes: cyclic peptides (microcystin-LR, microcystin-RR and nodularin), alkaloids (cylindrospermopsin and anatoxin-a) and three isomeric non-protein amino acids (β-methylamino-l-alanine, 2,4-diaminobutyric acid and N-(2-aminoethyl)glycine). Separation was achieved by using an acidic background electrolyte consisting of 2 M formic acid and 20% acetonitrile in water. Parameters affecting MS/MS detection and the sheath-liquid interface were also studied. Finally, a combination of pH-junction, field-amplified sample stacking (FASS) and acid barrage as online preconcentration strategies, was employed to improve sensitivity and efficiency. The online preconcentration applied, in combination with a dual cartridge solid-phase extraction (SPE) system, allows to obtain limits of detection in the very low range of µg·L−1 for these multiclass cyanotoxins in reservoir water samples (from 0.005 to 0.10 µg·L−1). Furthermore, for the first time cyanotoxins are analysed in spinach samples through CE-MS/MS using the same SPE procedure, following lyophilisation and solid-liquid extraction with 6 mL 80 % aqueous MeOH.Las cianotoxinas constituyen un grupo de metabolitos secundarios tóxicos, cuya presencia en cualquier masa de agua supone un importante riesgo para la salud. Además, los organismos avanzados, como las plantas comestibles expuestas a estas toxinas, son una posible vía de exposición humana. La química analítica verde exige técnicas analíticas respetuosas con el medio ambiente. En este sentido, proponemos el uso de electroforesis capilar acoplada a espectrometría de masas en tándem (CE-MS/MS) para determinar una mezcla de ocho cianotoxinas pertenecientes a tres clases diferentes: péptidos cíclicos (microcistina-LR, microcistina-RR y nodularina), alcaloides (cilindrospermopsina y anatoxina-a) y tres aminoácidos isoméricos no proteicos (β-metilamino-l-alanina, ácido 2,4-diaminobutírico y N-(2-aminoetil)glicina). La separación se logró utilizando un electrolito ácido que consistía en ácido fórmico 2 M y acetonitrilo al 20 % en agua. También se estudiaron los parámetros que afectan la detección MS/MS. Finalmente, se empleó una combinación de unión de pH, preconcentración de muestras amplificada en campo (FASS) y bombardeo ácido como estrategias de preconcentración en línea para mejorar la sensibilidad y la eficiencia. La preconcentración en línea aplicada, en combinación con un sistema de extracción en fase sólida (SPE) de doble cartucho, permite obtener límites de detección en el rango de µg/L para estas cianotoxinas multiclase en muestras de agua de embalses (de 0,005 a 0,10 µg/L). Además, por primera vez se analizan las cianotoxinas en muestras de espinacas mediante CE-MS/MS utilizando el mismo procedimiento SPE, tras liofilización y extracción sólido-líquido con 6 ml de MeOH acuoso al 80 %.MCIN/AEI /10.13039/501100011033 PID2021-1278040B-I00“FEDER Una forma de hacer Europa”Junta de Andalucía PROYEXCEL_00195Proyecto PID2021-1278040B-I00Universidad de Granada / CBU

Implementing the Use of Collision Cross Section Database for Phycotoxin Screening Analysis

The increased consumption of blue-green algae (BGA)-based dietary supplements has raised concern about their food safety, especially about cyanotoxin presence. The hyphenation of liquid chromatography with ion mobility mass spectrometry represents a relevant tool to screen several compounds in a large variety of food matrices. In this work, ultrahigh-performance liquid chromatography coupled to traveling wave ion mobility spectrometry/quadrupole time-of-flight mass spectrometry (UHPLC-TWIMS-QTOF) was employed to establish the first comprehensive TWIMS-derived collision cross section database (TWCCSN2) for phycotoxins. The database included 20 cyanotoxins and 1 marine toxin. Accurate m/z, retention times, and TWCCSN2 values were obtained for 81 adducts in positive and negative electrospray (ESI+/ESI–) modes. Reproducibility and robustness of the TWCCSN2 measurements were determined to be independent of the matrix. A screening was carried out on 19 commercial BGA dietary supplements of different composition. Cyanotoxins were confidently identified in five samples based on retention time, m/z, and TWCCSN2.The University of Parma through the action Bando di Ateneo 2021MUR-Italian Ministry of Universities and Research-D.M. 737/2021-PNR-PNRR−NextGenerationEU, (ii) from the Project PID2021-127804OB-I00Spanish MCIN/AEI/10.13039/501100011033ERDF A way of making Europe” and from the Andalousian Government (Project ref. PROYEXCEL_00195)The Grant (FPU17/03810) financed by MCIN/AEI/ 10.13039/501100011033, by “ESF Investing in your future”.Grant IJC2019-040989-I funded by MCIN/AEI/10.13039/501100011033Waters Italy for providing the Atlantis Premier BEH Z-HILIC colum

Aplicación de la espectrofluorimetría en fase sólida a la determinación de hidrocarburos aromáticos policíclicos en aguas

Se estudian nuevos métodos de análisis de hidrocarburos aromáticos policiclicos (hap) en aguas, mediante espectrofluorimetria en fase sólida (efs) dado su caracter carcinogenico. Se seleccionaron 12 hap y 3 absorbentes (dos hidrofilos y uno hidrofobo) para la fijación y estudio de los analitos. Se consiguen bajos limites de detección y pocas interferencias. A partir del estudio de fijación, longitudes de onda de los máximos de fluorescencia y demás condiciones experimentales se proponen cinco métodos de análisis mediante efs: Determinación de antraceno en aguas, empleando c-18 sílice por espectrofluorimetria convencional. Determinación de benzo(a)pireno fijado sobre sephadex g-25, por fluorescencia sincrónico. Determinación de la mezcla pireno y benzo(a)pireno fijados en sephadex g-25 mediante fluorescencia sincrónica derivada. Determinación simultanea de pireno, benzo(a)antraceno y benzo(a)pireno fijados sobre sephadex g-25 por fluorescencia sincrónica y, finalmente, determinación simultánea de acenafteno, fenantreno y fluoreno, fijados sobre sephadex g-25, mediante espectrofluorimetria sincrónica de ángulo variable. Los métodos propuestos se han aplicado al análisis de aguas de diversa procedencia comprobándose la validez de los métodos propuesto

Mortars, pigments and binding media of wall paintings in

Journal of Cultural Heritage 1 (2000) 19�28The Carrera del Darro is a street within the city of Granada, Spain, which is emblematic owing to the architectural value of its buildings, to its significance for the urban structure of the city and to the implications it has for the surroundings of the Alhambra. Our study concerns the chemical analysis of the mural paintings on four fac�ades, corresponding to numbers 23, 25, 27 and 29 of the Carrera del Darro. From the analysis of the mortar, it may be concluded that the composition is very similar, though not identical, in the four paintings studied: a limestone mortar. Ochre, white, black and red were used for the decoration of the four fac�ades; green pigment was also observed in the second decoration of no. 29. The results of the morphological examination and EDX microanalysis of the paint samples are shown. By means of the thermogravimetric analysis we established the existence of an organically derived compound. After the existence of an oleaginous binder had been discounted by gas chromatography:mass spectrometry (GC:MS) analysis, we continued with the extraction and determination of proteins by spectrophotometry analysis, detecting low levels of proteins in the paint on the four fac�ades analysed. The study was completed by evaluating the influence on the deterioration of the paintings by the possible surface presence of salts (such as nitrates or chlorides) and organic compounds

Determination of Multiclass Cyanotoxins in Blue-Green Algae (BGA) Dietary Supplements Using Hydrophilic Interaction Liquid Chromatography-Tandem Mass Spectrometry

In recent years, the consumption of blue-green algae (BGA) dietary supplements is increasing because of their health benefits. However, cyanobacteria can produce cyanotoxins, which present serious health risks. In this work we propose hydrophilic interaction liquid chromatography coupled with tandem mass spectrometry (HILIC-MS/MS) to determine cyanotoxins in BGA dietary supplements. Target toxins, including microcystin-leucine-arginine (MC-LR) and microcystin-arginine-arginine (MC-RR), nodularin, anatoxin-a and three non-protein amino acids, β-N-methylamino-L-alanine (BMAA), 2,4-diaminobutyric acid (DAB) and N-(2-aminoethyl)glycine (AEG), were separated using a SeQuant ZIC-HILIC column. Cyanotoxin extraction was based on solid–liquid extraction (SLE) followed by a tandem-solid phase extraction (SPE) procedure using Strata-X and mixed-mode cation-exchange (MCX) cartridges. The method was validated for BGA dietary supplements obtaining quantification limits from 60 to 300 µg·kg−1. Nine different commercial supplements were analyzed, and DAB, AEG, and MCs were found in some samples, highlighting the relevance of monitoring these substances as precaution measures for the safe consumption of these products

Multiclass cyanotoxin analysis in reservoir waters: tandem solid-phase extraction followed by zwitterionic hydrophilic interaction liquid chromatography-mass spectrometry

The presence of cyanobacteria and cyanotoxins in all water bodies, including ocean water and fresh water sources, represents a risk for human health as eutrophication and climate change are enhancing their level of proliferation. For risk assessment and studies on occurrence, the development of reliable and sensitive analytical approaches able to cover a wide range of cyanotoxins is essential. This work describes the development of an HILIC-MS/MS multiclass method for the simultaneous analysis of eight cyanotoxins in reservoir water samples belonging to three different classes according to their chemical structure: cyclic peptides (microcystin-LR, microcystin-RR and nodularin), alkaloids (cylindrospermopsin, anatoxin-a) and three non-protein amino acids isomers such as β-methylamino-L-alanine, 2,4-diaminobutyric acid and N-(2-aminoethyl)glycine). A SeQuant ZIC-HILIC column was employed to achieve the chromatographic separation in less than 12 min. Previously, a novel sample treatment based on a tandem solid-phase extraction (SPE) system using mixed cation exchange (MCX) and Strata-X cartridges was investigated with the aim of extracting and preconcentrating this chemically diverse group of cyanotoxins. The Strata-X cartridge, which was configured first in the line of sample flow, retained the low polar compounds and the MCX cartridge, which was at the bottom of the dual system, retained mainly the non-protein amino acids. The optimization procedure highlighted the importance of sample ion content for the recoveries of some analytes such as the isomers β-Nmethylamino-L-alanine and 2-4-diaminobutyric acid. Method validation was carried out in terms of linearity, limit of detection (LOD) and quantification (LOQ), recoveries, matrix effect and precision in terms of repeatability and intermediate precision. This work represents the first analytical method for the simultaneous analysis of these multiclass cyanotoxins in reservoir water samples, achieving LOQs in the very low range of 7·10-3 – 0.1 µg·L-1. Despite high recoveries obtained at the LOQ concentration levels (101.0-70.9%), relative standard deviations lower than 17.5% were achieved.RTI2018-097043-B-I00 financed by MCIN/ AEI /10.13039/501100011033/ FEDER “Una manera de hacer Europa”Spanish Network of Excellence in Sample preparation (RED2018-102522-T)FPU17/0381