Lung cancer is one of the main causes of death for thousands of people yearly around the world. Biomarker aldehydes, such as hexanal and heptanal, are compounds related to the development of lung cancer, which can be detected in the early stages of this disease. A methodology was proposed to determine these aldehydes in urine, with a new configuration associated with the sample preparation step. A novel strategy with a parallel-disposable pipette extraction (DPX)-cork device was used, offering a fast and affordable extraction methodology with analysis performed by high performance liquid chromatography with diode array detector. In optimization steps, multivariate and univariate designs were applied, providing the following conditions: urine sample centrifuged at 3500 rpm for 15 min, 30 µL and 6 min of dinitrophenylhydrazine impregnation, 10× urine diluted in ultrapure water, pH adjusted to 4.8, 7 extraction cycles with 1.5 min each, 30 mg of cork, 2 desorption cycles and solvent acetonitrile with 300 µL. Limits of detection were 0.13 ng mL-1 for both analytes and limits of quantification were 0.40 and 0.41 ng mL-1 for hexanal and heptanal, respectively. Intraday and interday precisions ranged from 4 to 21%. Relative recoveries ranged from 86 to 107%, assessed at three concentrations. Urine samples were analyzed, but the presence of aldehydes was not detected.

In this study, for the first time, histamine-functionalized magnetic nanoparticles (HIS-MNP) were used as sorbent phase combined with bar adsorptive microextraction (BAµE) for the determination of methylparaben (MP), ethylparaben (EP), propylparaben (PP), and butylparaben (BP) in water samples by high performance liquid chromatography coupled with diode array detection (HPLC-DAD). Extraction and desorption conditions, including desorption time and solvent, ionic strength effect and extraction time, were investigated. The extractions were performed for 90 min, 30% of NaCl and sample pH 5. Desorption was carried out using 250 μL of acetonitrile:methanol (25:75 v/v) for 30 min. The limits of detection (LODs) were of 1.5 μg L-1 and limits of quantification (LOQs) were 5.0 μg L-1 for all analytes. The intra-day precision ranged from 1% for EP, PP and BP to 3% for MP, EP, PP and BP. The inter-day precision ranged from 3% for EP to 18% for BP. The relative recoveries varied from 81 to 125%, and relative standard deviations (RSD) ranged between 1 and 16%.

An easy and efficient sample preparation method was developed for the determination of natamycin residues in wine samples by solvent extraction and ultra-high performance liquid chromatography coupled to tandem mass spectrometry (UHPLC-MS/MS) analysis. After choosing acetonitrile as extraction solvent, an experimental design was carried out with different amounts of C18 and primary secondary amine (PSA) sorbents in order to optimize the clean-up step. Validation results were satisfactory, with recoveries from 77 to 95% and relative standard deviation (RSD) lower than 10% for the spike levels 5, 10 and 20 µg L-1. Method limit of detection (LOD) and quantification (LOQ) were 1.5 and 5.0 µg L-1, respectively. The validated method proved to be an excellent analytical tool, with a total analysis time of 3 min. The method was applied in 10 Brazilian wine samples and no residues of natamycin were detected.

RESUMO: Diferentes frutos tropicais vêm sendo utilizados para o desenvolvimento de bebidas fermentadas, porém na bibliografia consultada há poucas referências sobre a produção de espumantes naturais de outras frutas diferentes da uva. Nesta perspectiva, o objetivo deste trabalho foi o desenvolvimento e a caracterização físico-química e volátil de um espumante natural de goiaba produzido pelo método champenoise. A determinação dos compostos voláteis foi realizada por cromatografia em fase gasosa acoplada a espectrometria de massas utilizando a técnica de microextração em fase sólida no headspace (HS-SPME) das amostras. Foram detectados 89 compostos voláteis, dos quais 51 foram identificados. Os ésteres foram os compostos voláteis predominantes em número, totalizando 26 compostos, seguido pelos álcoois (10), terpenos (9), cetonas (3) e ácidos (3). Compostos voláteis com possível atividade odorífera foram encontrados na bebida, dentre eles os ésteres octanoato de etila, 5-hexenoato de etila, acetato de fenetila, (E)-β-damascenona, (E)-cinamato de etila, acetato de 2-metil butila, 3-metil butanol, 3-(E)-hexenoato de etila e o 5-hexenoato de metila. O espumante natural produzido apresentou uma composição complexa de aroma frutado e floral. Além disso, a utilização do método tradicionalmente aplicado a uvas, o champenoise, proporcionou a fabricação de um espumante natural de goiaba com características físico-químicas equivalentes aos espumantes elaborados a partir de vinho.

ABSTRACT: Although different tropical fruit species have been used in the development of fermented beverages, there are only few references in the literature to the production of natural sparkling wines from fruits other than grapes. In this sense, the objective of the present research was the development and physicochemical and volatile characterization of a natural sparkling guava wine produced by the champenoise method. Volatile compounds were identified by gas chromatography coupled to mass spectrometry using the headspace solid-phase microextraction (HS-SPME) technique on samples. Eighty-nine volatile compounds were detected, of which 51 were identified. Esters were the predominant class of volatile compounds (a total of 26), followed by alcohols (10), terpenes (9), ketones (3), and acids (3). Volatile compounds with possible odoriferous activity were reported in the beverage, including ethyl octanoate, ethyl 5-hexenoate, phenethyl acetate, (E)-β-damascenone, (E)-ethyl cinnamate, 2-methyl butyl acetate, 3-methylbutanol, ethyl 3-(E)-hexenoate, and methyl 5-hexenoate. Natural sparkling guava wine produced showed a complex composition of fruity and floral aromas. Furthermore, the use of the champenoise method, traditionally applied to grapes, enabled the manufacture of a natural sparkling guava wine with physicochemical characteristics equivalent to those of sparkling wines made from grapes.

An effective analytical method for pesticides multiresidue determination in grape samples was developed and validated. A modified quick, easy, cheap, effective, robust and safe (QuEChERS) method was used to extract the target compounds. Several sorbent materials were tested for the clean-up step using dispersive solid phase extraction (d-SPE) and Florisil® was selected. Samples extracts were evaporated before injection in the gas chromatography with mass spectrometry (GC-MS) system in order to improve detectability. Recoveries from blank samples spiked at 0.04, 0.3 and 1.0 mg kg−1 ranged from 95 to 102% with relative standard deviation (RSD) from 1.3 to 19.7%. Method limits of detection (LODm) and quantification (LOQm) ranged from 0.006 to 0.012 and 0.02 to 0.04 mg kg−1, respectively. The positive matrix effect caused an increase in the peak areas of all compounds and matrix matched calibration curve linearity (coefficient of determination, r2) was higher than 0.98 for all target analytes. The validated method was successfully applied for the determination of 19 pesticides in grape samples.