RESUMO

In this work, a novel analytical methodology for the extraction and determination of polycyclic aromatic hydrocarbon derivatives, nitrated (NPAH) and oxygenated (OPAH), in bee honey samples was developed. The extraction approach resulted in being straightforward, sustainable, and low-cost. It was based on a salting-out assisted liquid-liquid extraction followed by liquid chromatography-tandem mass spectrometry determination (SALLE-UHPLC-(+)APCI-MS/MS). The following figures of merit were obtained, linearity between 0.8 and 500 ng g-1 for NPAH and between 0.1 and 750 ng g-1 for OPAH compounds, coefficients of determination (r2) from 0.97 to 0.99. Limits of detection (LOD) were from 0.26 to 7.42 ng g-1 for NPAH compounds and from 0.04 to 9.77 ng g-1 for OPAH compounds. Recoveries ranged from 90.6% to 100.1%, and relative standard deviations (RSD) were lower than 8.9%. The green assessment of the method was calculated. Thus, the Green Certificate allowed a classification of 87 points. This methodology was reliable and suitable for application in honey samples. The results demonstrated that the levels of nitro- and oxy-PAHs were higher than those reported for unsubstituted PAHs. In this sense, the production chain sometimes transforms foods as direct carriers of contaminants to consumers, representing a concern and demonstrating the need for routine control.

RESUMO

A green methodology was developed for the analysis of ten heterocyclic aromatic amines (HAAs) in biomass samples from cigarette combustion such as mainstream smoke, paper ashes, as well as tobacco and paper wraps. The cellulose filter used for sample collection was also evaluated. This strategy was based on ultrasound-assisted extraction (UAE) associated with a solid-phase extraction procedure employing multi-walled carbon nanotubes (MWCNTs-SPE) as a cleanup step followed by ultra-high-performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS). Under optimal experimental conditions, the linearity of the method was in the range from 0.08 to 160 ng cig-1, with correlation coefficients (R2) higher than 0.991. The limits of detection resulted to be between 0.03 and 0.63 ng cig-1. Concentrations of the HAAs in the mainstream smoke were from 5.7 to 145.2 ng cig-1 and in paper ashes from 0.1 to 0.6 ng cig -1, while in tobacco were between 1.0 and 38.5 ng cig-1. Meanwhile, no HAA contribution was observed in the case of paper wraps and the filter used for sample collection. The knowledge of the presence and the concentration levels of the selected HAAs in each cigarette's physical component after its combustion is essential to understand the formation processes and contribution during cigarette burning. Besides, this is the first report about the presence of some HAAs in the proposed samples. Finally, a comparative study was employed to classify the sustainability of several recent approaches for HAA extraction from cigarette combustion samples using Green Certificate as a metric tool.

Assuntos

RESUMO

In this study, a novel, simple, and highly sensitive analytical procedure for the quantitative evaluation of oxygenated and nitrated polycyclic aromatic hydrocarbons in volcanic ash samples based on dispersive solid-liquid microextraction (DSLME) coupled to ultra high-performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) was developed. Diverse chemometric tools were applied to optimize DSLME working conditions. Thus, a linear calibration curve for all the target analytes in the concentration range from 0.01 to 100 µg g-1 (r2 > 0.994) was obtained. The limits of detection for all the compounds were between 14.6 and 56.0 pg g-1, with high reproducibility (relative standard deviation (RSD) was below 8.1% for all the analytes). Additionally, recoveries ranged from 94.2 to 100%. The applicability of the method was evaluated and the feasibility of the existence of nitrated and oxygenated-PAHs in volcanic ashes at ultra-trace levels was demonstrated, which reveals an unknown source of distribution of these pollutants to the environment. Graphical Abstract.

Assuntos

RESUMO

A novel dispersive liquid-liquid microextraction based on solidification of floating organic droplet combined with ultrasound assisted back extraction for the determination of four heterocyclic aromatic amines in natural water samples prior ultra high-performance liquid chromatography-tandem mass spectrometry was developed. The analytes were extracted from the water samples by a dispersive liquid-liquid microextraction procedure based on solidification of floating organic drop, which was performed by a mixture composed by a less dense than water extraction solvent, 1-undecanol, and a dispersive solvent, methanol. After that, a novel ultrasound assisted back extraction step was performed in order to make the clean-up/enrichment procedure compatible with the detection requirements. Under optimum conditions, linearity ranged from 2.2 to 50ngmL-1, with enrichment factors from 130 to 136-folds. Thus limits of detection between 0.7 and 2.9ngmL-1 were obtained. Precision of the method was evaluated in terms of repeatability, relative standard deviations varied from 4.3% to 6.7%. Relative recoveries ranged from 92% to 106% for all analytes. The satisfactory performance demonstrated that the proposed methodology has a strong potential for application in the multi-residue analysis of heterocyclic aromatic amines present in complex environmental matrices.

RESUMO

El uso de nuez o maní en la elaboración de barras de cereales representa un posible riesgo de inestabilidad durante su almacenamiento debido al alto contenido de ácidos grasos insaturados de su aceite los que al oxidarse son una de las principales causas de deterioro. El desarrollo de nuevos productos alimenticios tipo snack implica el uso de envases que deben dar protección contra el daño provocado por la luz y reducción de la concentración de oxígeno en su interior. El objetivo de esta investigación fue evaluar los cambios físicos, químicos y sensoriales en el almacenamiento de barras de cereal con maní o nuez y cotiledón de algarrobo sometido a dos tratamientos térmicos, envasadas en celofán o polipropileno opaco. Se elaboraron 4 tipos de barras con 6 por ciento de cotiledón de algarrobo tratado por microondas o tostado en placa calefactora. y con 18 por ciento de maní o nuez. Las barras se almacenaron por 90 días a temperatura ambiente y cada 30 días se midió humedad, índice de peróxidos, actividad de agua, calidad y aceptabilidad sensorial. Los contenidos de peróxidos obtenidos (4,9-13,8 meq/kg de aceite) indican que la vida útil de las barras en todos los tratamientos estudiados fue de 90 días. Los materiales de envases utilizados permiten mantener las barras de cereales en buenas condiciones de humedad (7,4-11,2 por ciento), actividad de agua, (0,50-0,65) y aceptabilidad sensorial durante 3 meses

Assuntos