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In this study, the determination of fructose, glucose and sucrose by capillary electrophoresis (CE) was investigated. The tendency of the analyte to undergo electromigration dispersion and the buffer capacity were evaluated using the Peakmaster(®) software and considered in the optimization of the background electrolyte, which was composed of 20 mmol L(-1) sorbic acid, 0.2 mmol L(-1) CTAB and 40 mmol L(-1) NaOH at pH 12.2. Under optimal CE conditions, the separation of the substances investigated was achieved in less than 2 min. The detection limits for the three analytes were in the range of 0.022 and 0.029 g L(-1) and precision measurements within 0.62-4.69% were achieved. The proposed methodology was applied in the quantitative analysis by direct injection of in honey samples to determine the main sugars presents. The samples were previously dissolved in deionized water and filtered with no other sample treatment. The mean values for fructose, glucose and sucrose were in the ranges of 33.65-45.46 g 100g(-1), 24.63-35.06 g 100g(-1) and <0.22-1.32 g 100g(-1), respectively. The good analytical performance of the method makes it suitable for implementation in food laboratories for the routine analysis of honey samples.

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One of the most useful methods for elimination of solid residues of health services (SRHS) is incineration. However, it also provokes the emission of several hazardous air pollutants such as heavy metals, furans and dioxins, which produce reactive oxygen species and oxidative stress. The present study, which is parallel to an accompanied paper (Avila Jr. et al., this issue), investigated several enzymatic and non-enzymatic biomarkers of oxidative stress in the blood (contents of vitamin E, lipoperoxidation = TBARS, reduced glutathione = GSH, oxidized glutathione = GSSG, and activities of glutathione S-transferase = GST, glutathione reductase = GR, glutathione peroxidase = GPx, catalase = CAT and superoxide dismutase = SOD), in three different groups (n = 20 each) exposed to airborne contamination associated with incineration of SRHS: workers directly (ca. 100 m from the incinerator) and indirectly exposed (residents living ca. 5 km the incineration site), and controls (non-exposed subjects). TBARS and GSSG levels were increased whilst GSH, TG and alpha-tocopherol contents were decreased in workers and residents compared to controls. Increased GST and CAT activities and decreased GPx activities were detected in exposed subjects compared to controls, while GR did not show any difference among the groups. In conclusion, subjects directly or indirectly exposed to SRHS are facing an oxidative insult and health risk regarding fly ashes contamination from SRHS incineration.

This study reports the development and validation of a fast capillary electrophoresis method for cation determination in honey samples and the classification of honey by geographical origin using Principal Components Analysis (PCA). The background electrolyte (BGE) was optimized using the Peakmaster(®) software, which evaluates the tendency of the analytes to undergo electromigration dispersion and the BGE buffer capacity and conductivity. The final BGE composition was defined as 30 mmol L(-1) imidazole, 300 mmol L(-1) acetic acid and 140 mmol L(-1) Lactic acid, at pH 3,0, and the separation of K(+), Na(+), Ca(2+), Mg(2+) and Mn(2+) using Ba(2+) as the internal standard was achieved in less than 2 min. The method showed satisfactory results in terms of linearity (R(2)>0.999), the detection limits ranged from 0.27-3.17 mg L(-1) and the quantification limits ranged from 0.91-10.55 mg L(-1). Precision measurements within 0.55 and 4.64%RSD were achieved and recovery values for the analytes in the honey samples ranged from 93.6%-108.6%. Forty honey samples were analyzed to test the proposed method. These samples were dissolved in deionized water and filtered before injection. The CE-UV reliability in the cation analysis in the real sample was compared statistically with ICP-MS methodology. No significant differences were found, with a 95% confidence interval between the methodologies. The PCA showed that the cumulative variance for the first two principal components explain more than 85% of the variability of the data. The analytical data suggest a significant influence of the geographical origin on the mineral composition.