Gas chromatography-tandem mass spectrometry multi-residual analysis of contaminants in Italian honey samples.

Contaminants belonging to various classes, including polychlorobiphenyls (PCBs), polycyclic aromatic hydrocarbons (PAHs), organochlorine pesticides (OCPs), organophosphorus pesticides (OPPs), pyrethroid insecticides (PYRs), fungicides (Fs), herbicides (Hs), synergists (SYNs) and insect growth regulators (IGRs) were analysed simultaneously in honey samples using a new simultaneous, easy and rapid method based on a liquid-liquid extraction with a mixture of n-hexane and ethyl acetate. It allowed recoveries in the range 80-137%, with limits of detection (LODs) between 0.10 and 5.21 ng g-1, showing a good sensitivity and accuracy. All the analysed Italian honeys showed the presence of residues of OPPs; PAHs were in 46.8% of the samples and PCBs were always below the LODs; 53.2% of the samples were contaminated by OCPs, PYRs, SYNs and IGRs. In addition, 46.8% of the samples exceeded the maximum residue limits (MRLs) established by the European Community in honey for chlorfenvinphos (cis + trans), TPP, γ-HCH, tebuconazole, coumaphos and τ-fluvalinate (cis + trans).

Chemometric analysis of minerals and trace elements in Sicilian wines from two different grape cultivars.

Chemometric analysis are used for food authenticity evaluation, correlating botanical and geographical origins with food chemical composition. This research was carried out in order to prove that it is possible linked red wines to Nero d'Avola and Syrah cultivars of Vitis vinifera according to their mineral content, while the values of the physical and chemical parameters do not affect relevantly this discrimination. The levels of mineral elements were determined by ICP-OES and ICP-MS. Samples from cv Nero d'Avola had the highest content of Zn, Cr, Ni, As and Cd, whereas the highest mineral concentration in cv Syrah samples was represented by K, Mg, Cu, and Sb. The research highlights that it is possible linked red wines to Nero d'Avola and Syrah cultivars of V. vinifera according to their mineral contents, adding knowledge to the determination studies of the wine botanical origin.

High performance liquid chromatography coupled with atmospheric pressure chemical ionization mass spectrometry for sensitive determination of bioactive amines in donkey milk.

In the present study we report on the optimization and validation of a sensitive high performance liquid chromatography atmospheric pressure chemical ionization mass spectrometry (HPLC-APCI-MS) method for the determination of 8 bioactive amines (histamine, tyramine, tryptamine, 2-phenylethylamine, cadaverine, putrescine, spermidine and spermine) in donkey milk samples. The method involves donkey milk pre-treatment to remove proteins and pre-column dansylation of the amines. HPLC in reversed phase mode has been used for bioactive amines separation and the operating condition of the APCI-MS system proved to be powerful and very efficient for peak assignment. The separation was accomplished in a short time with an excellent resolution for all the amine peaks. Quantification was carried out by monitoring the characteristic [M+H](+) ion of each amine derivative. The method sensitivity, linearity and repeatability were assayed with satisfactory results. The detection limits of the analysed amines ranged from 0.5 microg L(-1) to 15 microg L(-1); the highest LOD was for spermine. Also remarkably good recovery values were obtained; at the lowest spiking level (1 microg L(-1)) the percent mean recoveries ranged from 77.7 to 109.7. Furthermore, as the investigations relate to a complex matrix as donkey milk, suitable studies on matrix effect were performed. Finally, the developed and validated method was applied to analyse 13 donkey milk samples. Among the identified bioactive amines, putrescine, spermine and spermidine proved to be the main amines in donkey milk. Their concentration levels in the present study were lower than the values determined in mature human, cow and sow milk.

[Hormonal, auxological and clinical follow-up in children with connatal HIV infection: personal records]. / Valutazione plurispecialistica per un follow-up clinico, auxologico ed endocrino di pazienti con infezione connatale da HIV: dati di una casistica personale.

Auxological and endocrinological complications frequently occur in children with connatal HIV infection. These complications seem to be related both to the infection itself and the antiretroviral therapy. Many children consequently show height-weight and pubertal retardation without any evidence of hormonal deficit. We studied 10 children with connatal HIV infection who were enrolled in this analysis and followed up for 7 years in order to evaluate their height-weight growth, pubertal maturation, bone age progression and hormonal pattern [basal Growth hormone (GH) and GH after Clonidine or Insulin stimulation, Insulin-like Growth Factor 1 (IGF-1), Insulin-like Growth Factor Binding Protein 3 (IGFBP-3), FSH, LH, ACTH and Cortisol, TSH, fT4, T4, T3, Ab-TGO, Leptin]. Three children showed a height lower than 3rd centile during the first two years of their life and in prepubertal age, with recurring improvement in their growth rate. Weight growth was very compromised in one girl, remaining firmly lower than 3rd centile during the follow-up. Three children presented a weight lower than 3rd centile until they were two years old. However, a height growth rate higher than 10th centile was found in nine children throughout the follow-up, while it was pathological in five children. The blood level of Leptin was higher at the beginning of the study: 0.82 - 11.68 ng/l (M+/-DS: 3.29+/-4.15) than at its conclusion: 0.2 - 3 ng/l (M+/-DS: 1.65+/-1.01). There was a statistically significant correlation between leptinemia and the CD4/CD8 count (p: 0.010; r: 0.916) and the CDC classification (p: 0.006; r: 0.937), indicating a strong relationship with the degree of virological and immunological impairment. The authors stress the importance of a careful height-weight growth rate control in HIV-infected children, as it reflects the clinical and virological course of the disease. Adequate control of the infection allows physiological growth in most patients. Moreover, we emphasize the utility of IGFBP-3 and IGF-1 measurements, since they represent growth markers which are more exact and better capable of reproduction than GH.

The biodegradation efficiency on diesel oil by two psychrotrophic Antarctic marine bacteria during a two-month-long experiment.

Two psychrotrophic bacterial strains isolated from Antarctic seawaters were investigated for their capability to degrade commercial diesel oil. The efficiency of hydrocarbon utilization was studied at 4 and 20 degrees C over a period of two-months. Strains were cultured in a mineral liquid medium supplemented with diesel oil as the sole source of carbon and energy. The viable counts for the bacterial abundance estimation and the culture extractions for the subsequent gas-chromatographic analysis were carried out simultaneously. The biodegradation efficiency was higher at 20 degrees C than at 4 degrees C for both strains and the decrease in hydrocarbon concentrations reached more than 85% after 60 days of incubation at 20 degrees C. Our results suggest the possible exploitation of these two bacterial strains in future biotechnological processes, directly as field-released micro-organisms both in cold and temperate contaminated marine environments.

Pesticide and plasticizer residues in bergamot essential oils from Calabria (Italy).

Organophosphorus and organochlorine pesticides, phosphorated plasticizers, chloroparaffins and phthalate esters contamination in bergamot essential oils produced in Calabria in the crop years 1999-2000 was studied by HRGC in connection with detectors FPD, ECD, MS. Residues of dicofol and tetradifon were found in oils from both crop years. The mean dicofol concentration was 0.26 mg/l in samples from 1999 and 0.20 mg/l in those from 2000; the mean tetradifon content was 0.06 mg/l for both the crop years. Among plasticizers, residues of diisobutyl phthalate, di-n-butyl phthalate, and bis(2-ethylhexyl) phthalate were found in samples from crop years 1999 and 2000, the mean content were 1.22 and 1.23 mg/l, 1.51 and 1.65 mg/l, 1.38 and 1.42 mg/l respectively.

Determination of selenium content in different types of seed oils by cathodic stripping potentiometry (CSP).

Seed oils are consumed worldwide; moreover, they are used in the alimentary, cosmetic, pharmaceutical, and chemical industries. Due to their diffusion, it is interesting to investigate the presence of important micronutrients such as selenium in seed oils. The aim of this work was to develop a rapid, precise, and sensitive cathodic stripping potentiometry (CSP) method to determine the concentration of selenium in different types of seed oils. Selenium was extracted from the oily matrix by concentrated hydrochloric acid treatment at 90 degrees C. The analysis was executed by applying an electrolysis potential of -150 mV for 60 s and a constant current of -30 microA. Under these conditions, detection limits of <0.5 ng g(-1) were obtained. The method reproducibility (expressed as total RSD %) spanned from 0.2 to 0.8%. Recoveries ranged from 92.1 to 97.5%, providing evidence that selenium quantification remained unaffected by the extraction procedure described. The results obtained with the proposed method were compared with those obtained via graphite furnace atomic absorption spectroscopy (GFAAS), a common method for determining selenium. The results of the two methods agreed within 93.5-107.7%. The mean amounts of selenium found were 313.0 +/- 2.0, 458.3 +/- 1.3, 224.6 +/- 0.9, 99.5 +/- 0.8, 332.2 +/- 0.5, 144.0 +/- 0.7, and 295.5 +/- 1.2 ng g(-1), respectively, in peanut, soybean, sunflower, rice, corn, grapestone, and seed oils.

Simultaneous determination of Cd(II), Cu(II), Pb(II), and Zn(II) in citrus essential oils by derivative potentiometric stripping analysis.

Citrus essential oils are widely used in the food, cosmetics, and pharmaceutical industries, so the determination of heavy metals content is of great importance to guarantee their quality. The present work deals with the quantification of Cd(II), Cu(II), Pb(II), and Zn(II) in different varieties of citrus essential oils, using derivative potentiometric stripping analysis. Two different metals extraction procedures, involving concentrated hydrochloric acid treatment and acid-alcoholic dissolution, are tested on lemon, mandarin, sweet orange, and bergamot essential oils, and they give very similar results. Cd(II), Cu(II), Pb(II), and Zn(II) recovery tests spanned from 95 to 100.50%, providing evidence that metals quantification remained unaffected by the cleanup steps of the two procedures. The repeatability of the hydrochloric acid extraction method, applied on different varieties of essential oils, is >95.00% for Cd(II), Cu(II), Pb(II), and Zn(II), whereas the repeatability of the acid-alcoholic dissolution method is >93.00% for Cu and Cd only in lemon oil. Detection limits obtained for the four analytes, using both procedures, ranged from 0.10 to 0.98 ng g(-)(1) in lemon, mandarin, sweet orange, and bergamot essential oils.

Luminescence Properties of Platinum(II) Dithiooxamide Compounds.

Tight contact ion pairs of general formula {Pt(H(2)-R(2)-dto)(2)(2+),(X(-))(2)} have been prepared, and their absorption spectra and luminescence properties (at room temperature in dichloromethane fluid solution and at 77 K in butyronitrile rigid matrix) have been studied (dto = dithiooxamide; R = methyl, X = Cl (1); R = butyl, X = Cl (2); R = benzyl, X = Cl (3); R = cyclohexyl, X = Cl (4); R = cyclohexyl, X = Br (5); R = cyclohexyl, X = I (6)). The absorption spectra of all the compounds are dominated by moderately strong Pt(dpi)/S(p) to dithiooxamide (pi) charge transfer (Pt/S --> dto CT) bands in the visible region (epsilon in the 10(4)-10(5) M(-)(1) cm(-)(1) range). Absorption features are also present at higher energies, due to pi-pi transitions centered in the dto ligands (ligand centered, LC). All the compounds exhibit a unstructured luminescence band in fluid solution at room temperature, with the maximum centered in the 700-730 nm range. The luminescence bands are blue-shifted about 4000 cm(-)(1) on passing to the rigid matrix at 77 K. Luminescence lifetimes are on the 10(-)(8)-10(-)(7) s time scale at room temperature and 1 order of magnitude longer at 77 K. Luminescence is assigned to triplet Pt/S --> dto CT excited states in all cases. Compounds 3-6 also exhibit a second higher-energy luminescence band at room temperature, centered at about 610 nm, attributed to a LC excited state. Charge transfer interactions between halides and dto ligands destabilize dto-centered orbitals, affecting the energy of Pt/S --> dto CT transitions and states. The X counterions and X --> dto CT levels are proposed to play a role in promoting excited state conversion between LC and Pt/S --> dto CT levels. The R substituents on the nitrogen atoms of the dto ligands influence the absorption and photophysical properties of the compounds, by affecting proximity of the ion pairs. The possibility to functionalize the R substituents may open the way to interface these luminescent compounds with desired substrates and to construct supramolecular assemblies.