Voltammetric determinations of platinum and rhodium in particulate of Palermo (Italy) area

Traffic has an important impact on the air quality which affects both the environmental and human health. Since the introduction of PGE-containing catalytic converters, a number studies have been undertaken to determine the effects of PGE emissions on human and to environment. This requires the development of good analytic methods to measure Pt and Rh concentrations in environmental matrices, as well to estimate background concentrations. In this paper are presented the results concerning Pt and Rh concentrations in PM10 samples collected at five stations within the urban area of Palermo. The highest mean values (Pt= 13 pg/m3, Rh=9.8 pg/m3) were recorded at an urban station, and the lowest …

Equilibri di idrolisi ad alta temperatura

L’idrolisi di molti ioni metallici dà spesso luogo alla formazione di specie mono e polinucleari. Nel caso di cationi quali Ga(III), Al(III), Cr(III) le difficoltà riscontrate nella raccolta dei dati sono essenzialmente dovute alla lentezza degli equilibri in studio; ciò ha causato disaccordo tra i dati di letteratura sia sulla natura delle specie formate che sulla loro stabilità. In assenza di un opportuno catalizzatore per lo studio a temperatura ambiente, l’unico modo per aumentare la velocità delle reazioni è aumentare la temperatura, in modo tale da ottenere stati di reale equilibrio. Un aumento della temperatura rende complicata la termostatazione dei reattivi e la loro aggiunta dall’…

la semicella Zn(Hg)/Zn++ ed alcune sue applicazioni analitiche

Unusual oxidation states of cations in aqueous solutions

Determinazione degli elementi in tracce negli alimenti per celiaci tramite ICP-MS

The complex formation equilibria between Cd(II), Pb(II) and iminodiacetic acid in NaClO4 0.93 Mw at 25°C

The Formal Redox Potential of the Ti(IV, III) Couple at 25 °C in 1 M HCl 2 M NaCl Medium

The formal redox potential of the Ti(IV, III) couple has been determined at 25 degrees C in 1 M HCl, 2 M NaCl aqueous medium, by emf measurements of a junction-free cell with glass and mercury electrodes. Ti(III) and Ti(IV) concentrations were changed by controlled electrolysis. The mean value of the searched formal potential, in a large range of total titanium concentration, is 9 +/- 1 mV against the molar hydrogen electrode in the same ionic medium.

Platinum and rhodium in wine samples by using voltammetric techniques

For the first time, the concentrations of Pt and Rh in 42 different alcoholic beverages (white and red wines, vodka and brandy) produced in Italy, Malta and Gozo were investigated. Only the voltammetric techniques, in particular, differential Pulse Voltammetry (DPV/a) and Adsorptive Stripping Voltammetry (AdSV) were used for the determination of Pt and Rh respectively. Accuracy was tested with standard addition method and recoveries ranged from 90% to 98%. In analyzed wine samples, Pt and Rh concentrations are in the ranges from 3 to 470 μg L− 1and from 0.0006 to 0.36 μg L− 1respectively. We found a Pt/Rh ratios ranged from 37 to 180,000, in quite disagreement with the ratio in …

Le proprietà acide dello ione uranile in soluzione acquosa LiClO4 3,6 molale a 75 e 100°C

Aldehydes measurements in public indoor environments in Palermo (Italy) using voltammetry.

Studies on indoor air quality are important since people spend more than 80% of life in confined environments, thus it is necessary to evaluate indoor contaminant concentrations and distributions for assessing total human exposure to them (Mannino and Orecchio, 2008; Orecchio, 2011). Aldehydes are indoor and outdoor chemical pollutants of particular interest due to their potential impact on health. Formaldehyde is usually the most abundant aldehyde in air and also the most studied since it is classified as human carcinogen. It is well known that formaldehyde is directly emitted from building materials, wood combustion, cigarette smoking, and is used as a bactericidal agent. One purpose of t…

Formaldehyde and total aldehydes in indoor air of public environments by voltammetry

The proposed method involves active sampling, where a sampling pump is used to pull air through a solution and voltammetric analysis of the obtained solutions. No interferences have been observed. In addition, very little sample preparation is required. Analyses were performed in 19 indoor stations and one in outdoor. Measurements were carried out on University environments: Museum of Chemistry, Zoological Museum, libraries, laboratories, corridors, meeting rooms, photocopying room, machine shop and terrace. Formaldehyde concentrations in analyzed samples ranged from 2.6 to 85 μg m-3 (median = 32 μg m-3), while the sum of others aldehydes ranged from 2 to 25 μg m-3 (median =2.4 μg m-3). In …

Determinazione spettrofotometrica simultanea della durezza calcica e totale in acque potabili

The Formal Potential of the Ti(IV-III) Couple at 25°C in the TiCl4, TiCl3, HCl, NaCl Mixtures at 3 M tital Cl-.

The acidic properties of the uranyl ion in LiClO4 aqueous solutions 3.6 molal at 75 and 100°C

Voltammetric determination of platinum il leaves of Nerium oleander L. ; Preliminary data on assessment of air quality in the Palermo

PLATINUM AND RHODIUM IN WINES

Stati di ossidazione insoliti di cationi metallici in soluzione acquosa

Vanadium and molybdenum concentrations in particulate from Palermo (Italy): analytical methods using voltammetry

The main purpose of this work was to develop a reliable method for the determination of vanadium (V) and molybdenum (Mo) in atmosphere particles or aerosols because they can not be readily measured using conventional techniques. For this research, 30 particulate samples were collected from five different stations located at Palermo, Italy. We used the catalytic adsorptive stripping voltammetry and differential pulsed voltammetry to measure Vand Mo in atmospheric particulate, respectively. The represented method includes advantages of high sensitivity, high selectivity, simplicity, reproducibility, speed and low costs. The quantification limits for V and Mo are, respectively, 0.57 and 0.80 n…

Quantification of Platinum in Edible Mushrooms Using Voltammetric Techniques

Edible mushrooms are a food source with interesting nutritional values. The chief objective of this research was to develop a consistent method for the quantitative ultra-trace analysis of Pt in mushrooms, which is complex because it cannot be readily quantified by common analytical procedures. This research is one of the first analytical methods to establish Pt amount in these vegetables. In this research, 28 different edible mushroom samples from Italy were investigated. Determination of Pt in mushrooms was completed using Differential Pulse Voltammetry (DPV). In this study, we applied the standard addition method because there are no certified reference mushrooms containing platinum grou…

DETERMINATION OF MACRO ELEMENTS IN GLUTEN-FREE FOOD FOR CELIAC PEOPLE BY ICP-OES

This paper is the first analytical approach to the study of seven nutrients in the gluten-free foods for celiac people. The ICP-OES technique was used. One of the advantages about the use of ICP-OES for this characterization is the high selectivity and low interferences for studied elements. The concentration values of K, Li, Sr, Na, Ca, Mg and Al in seventeen gluten-free food samples are reported. Considering the average concentrations of the elements analyzed, excluding lithium, in the present study it can be concluded that they are inadequate if compared with the recommended daily intake by international organisms, providing only from 1.5 to 20% of the RDI for the essential metals. In pa…

Voltammetric method with microwave-assisted sample digestion for the determination of platinum in biological matrices: preliminary data on pharmacokinetic study of hepatic perfusion with oxaliplatin

CHEMICAL CHARACTERIZATION OF ANCIENT LITURGICAL VESTMENT (CHASUBLE) BY ICP-OES

Complex Formation of the Uranyl (UO22+) Ion with the Diethylene Triaminopentaacetate (DTPA) Ligand at 25 °C in 3 M Sodium Perchlorate

The complex formation between the uranyl (UO22+) ion and the diethylene triaminopentaacetate ligand (DTPA) has been investigated at 25 °C, in a 3 M sodium perchlorate medium. The overall protonation constants βjH of the free ligand have been previously determined in this ionic medium: six protonated species (HjA), with j ranging from 1 to 6, together with the free anion A5− have been identified in the concentration range from (3·10−3 to 13·10−3) mol·kg−1. Four complex species, H2UO2A−, HUO2A2−, UO2A3−, and UO2AOH4−, have been identified in the total uranyl concentration range from (1.1·10−3 to 5.7·10−3) mol·kg−1, and their overall stability constants determined, keeping the metal to ligand …

II) Wood pellets for home heating can be considered environmentally friendly fuels? Heavy metals determination by inductively coupled plasma-optical emission spectrometry (ICP-OES) in their ashes and the health risk assessment for the operators

Abstract The aim of the present study was to determine the concentrations of twelve potentially hazardous elements in wood pellet ashes obtained by the combustion of 13 pellet brands for sale in Italy, the impact of adding the ashes to soils and health risk of operator due to dust exposure. Samples were analysed by Inductively Coupled Plasma Optical Emission Spectrometry. The concentrations of heavy metals in ashes from stoves ranged from 0.41 to 7.2 mg kg − 1 for As, from 1.3 to 12 mg kg − 1 for Sb, from 1.8 to 12 mg kg − 1 for Zn, from 0.23 to 0.8 mg kg − 1 for Pb, from 0.18 to 2.8 mg kg − 1 for Ni, from 0.09 to 1.0 mg kg − 1 for Cd, from 0.46 to 3.4 mg kg − 1 for Cr, from 0.94 to 2.7 mg …

Determination of trace elements in gluten-free food for celiac people by ICP-MS

Abstract This paper is the first analytical approach to the study of twenty heavy metals in the gluten-free foods for celiac people. Only the ICP-MS technique was used. One of the advantages about the use of ICP-MS for this characterization is the high sensitivity that improved the limits of quantification levels for some elements that are present at low quantities in some samples. The concentration values of As, Ba, Cd, Co, Cr, Cu, Fe, Hg, Mn, Mo, Ni, Pb, Sb, Se, Sn, V and Zn in seventeen gluten-free food samples are reported. The highest arsenic and molybdenum levels were measured in Rice noodle from China (0.088 and 0.47 mg kg − 1 , respectively). The highest concentrations of some metal…

Analytical Method for Quantification of Several Phthalate Acid Esters by Gas Chromatography-Mass Spectrometry in Coffee Brew Samples

Several phthalate acid esters (PAEs), often called phthalate esters or phthalates, are substances classified as harmful due to their carcinogenic and mutagenic properties, and moreover, as dangerous for humans because they interfere with the endocrine system. In general, phthalic esters are used as plasticizers for different polymers and more other consumer products. In the present study, we describe a simple method to quantify PAEs in coffee brew using a liquid-liquid extraction without purification processes through analysing the obtained organic phase by GCMS in the single ion monitoring mode. The totals of single PAEs, in coffee brew samples analysed by us, are in the range of 159-5305 …

The formal redox potential of the Yb(III,II) Couple at 0°C in 3.22 molal NaCl medium

Following our previous investigations on aqueous solutions of hypooxidized and iperoxidized species, we managed, by lowering the temperature of the solutions to 0 degrees C, to obtain, by electrochemical methods, Yb(II) and Yb(III) mixtures, enough stable to determine by a potentiometric method the formal redox potential of the Yb(IlI, II) couple. Its value, in a large range of total Ytterbium concentration, is -1233 +/- 3 mV against the molal hydrogen electrode in the 3.22 m NaCl medium.

Wood pellets for home heating can be considered environmentally friendly fuels? Polycyclic aromatic hydrocarbons (PAHs) in their ashes

This paper reports the results of the first quantitative investigations of PAHs in wood pellet ashes. Investigations were carried out into the fifteen PAHs identified by the US-Environment Protection Agency (US-EPA) as requiring priority monitoring; other non-US-EPA listed PAHs and perylene were also investigated. The total concentrations for the 17 investigated compounds, expressed as the sum of the concentrations (∑PAHs), in the ashes produced by the wood pellet combustion, ranged from 0.064mg kg-1 to 0.90mg kg-1 of dry weight with a means of 0.31mg kg-1. The lowest concentrations (<0.1mg kg-1) were measured in the conifer ash samples. Concentrations of PAHs found in this paper will al…

Discrimination of almonds (Prunus dulcis) geographical origin by minerals and fatty acids profiling

Twenty-one almond samples from three different geographical origins (Sicily, Spain and California) were investigated by determining minerals and fatty acids compositions. Data were used to discriminate by chemometry almond origin by linear discriminant analysis. With respect to previous PCA profiling studies, this work provides a simpler analytical protocol for the identification of almonds geographical origin. Classification by using mineral contents data only was correct in 77% of the samples, while, by using fatty acid profiles, the percentages of samples correctly classified reached 82%. The coupling of mineral contents and fatty acid profiles lead to an increased efficiency of the clas…

Il potenziale formale della coppia Ti(IV,III) a 25°C nel mezzo HCl 1 M NaCl 2 M

Nell’ambito delle diverse coppie ossidoriduttive di un elemento in soluzione acquosa, vengono indicate come ipoossidate le specie appartenenti a quelle coppie il cui potenziale standard è inferiore a quello di riduzione dell’acqua ad idrogeno, e come iperossidate le specie che fanno parte di coppie con valore del potenziale di riduzione superiore a quello dell’ossigeno ad acqua. Si tratta in entrambi i casi di specie termodinamicamente poco stabili che si trasformano rispettivamente nella forma ossidata con evoluzione di idrogeno e nella forma ridotta con evoluzione di ossigeno. Tali processi sono modulati dall’attività idrogenionica della soluzione (Figura 1). Figura 1. Intervallo di stabi…

Analysis of Contaminants in Beverages

Abstract The main purpose of our researches, in the last years, was to develop reliable methods for the determination of emerging and old contaminants (Pt, Rh, V, Mo, polycyclic aromatic hydrocarbons (PAHs), etc.), at trace levels, in the solutions obtained from the mineralization or extraction of environmental and food matrices, because, in particular for metals, some of them cannot be readily analyzed using traditional method, for example, inductively coupled plasma-optical emission spectrometry and inductively coupled plasma with mass spectrometry techniques. Few data are available on the evaluations of Pt, Rh, V, and Mo concentrations, in food matrices, because have ever been carried ou…

The possible use of the half cell Zn(Hg)/Zn2+ in ionic equilibria studies

Dioxouranium(VI) hydrolysis at 75 and 100°C in 3.6 molkg-1 LiClO4

This work concerns the acidic properties of uranyl ion UO22+ at 75 and 100 °C in 3.6 molal (molkg-1 solvent) LiClO4 aqueous medium. The investigation was carried out by a coulometric-potentiometric technique. Direct and reverse acid base titrations were carried out in order to check the achievement of actual equilibrium conditions. Moreover, in order to reveal oversaturation conditions, a further check was carried out on clean saturated hydrolyzed solutions.

Gli spot test nell'analisi sistematica di alcuni cationi

Batch experiments for the determination of the Ti(IV,III) couple in 1 moldm-3 HCl, 2 moldm-3 NaCl medium at 25°C

The determination of the Ti(IV, III) redox couple formal potential in 1 M HCl 2 M NaCl medium at 25°C through batch experiments involving the preparation of Ti(IV) and Ti(III) mixtures via the reaction of Ti(IV) with Zinc amalgam, has been carried out with emf measurements in order to verify the correctness of the previous value that the authors obtained by a coulometric-potentiometric investigation in the same conditions. The results from the two independent methods are in good agreement: 9 ± 1 mV the first and 9 ± 2 the average batch result.

Platinum in indoor settled dust matter (homes and cars)

Abstract This paper presents a method for Pt analysis in indoor (homes and cars) settled dust, used as passive samplers, and the results relative to samples collected in the Sicilian area are used to evaluate the magnitude and distribution of concentrations inside common environments and the possible origins of the considered contaminant. The concentrations of platinum in settled indoor dust were measured by differential pulsed voltammetry (DPV). Concentrations of Pt in homes are in the range from 30 to 1460 μg kg − 1 d.w. while, in the vehicles from 30 to 1750 μg kg − 1 d.w. Considering the geoaccumulation index (I geo ), 42% of the settled dust sampled in homes could be classified as extr…

Speciation of vanadium in urban, industrial and volcanic soils by a modified Tessier method

Vanadium (V) concentrations in industrial, urban and volcanic soils were sequentially extracted using a modified Tessier's method. The voltammetric technique was used to determine V concentrations in solutions obtained from the various extraction steps. At the reference stations, the V concentrations (sum of four individual fractions) in soils ranged from 0.72 to 0.24 g kg(-1) dry weight (d.w.) with a mean value of 0.18 g kg(-1) d.w. V concentrations in soils of the Palermo urban area ranged from 0.34 to 2.1 g kg(-1) d.w., in the Milazzo (industrial) area between 0.26 and 5.4 g kg(-1) d.w. and in the volcanic area near Mt. Etna from 0.91 to 2.9 g kg(-1) d.w. When the V concentrations around…

Il potenziale redox della coppia Ti(IV,III) a 25°C nel mezzo HCl 1 M NaCl 2 M

Platinum levels in urban soils from Palermo (Italy); Analytical method using voltammetry

Abstract A fast accumulation of platinum in the environmental and biological matrices was observed in the last years and concern arose about potential environmental and health risks. The toxicity of platinum species has been investigated in various studies, some of their, especially the chlorinated ones, are very toxic and allergenic. Information of the acute toxicity of some Pt-chlorinated salts and evidence of DNA damage due to Pt exposure have been observed both in vitro and in vivo. Taking into account what is written above, the development of reliable analytic methods to measure very low Pt concentrations is required. In this work was developed a reliable method for the determination o…

Chemical characterization of ancient liturgical vestment (chasuble) by Inductively Coupled Plasma–Optical Emission Spectrometry (ICP–OES)

Abstract This paper presents the chemical characterization of the yarns of an ancient liturgical vestment (chasuble). The samples have been analyzed for Al, Ag, Au, Cd, Co, Cr, Cu, Ni, Pb and Zn using amounts always less than 1 mg by Inductively Coupled Plasma–Optical Emission Spectrometry (ICP-OES). Except a sample, silver is the most abundant element in all the yarns. In the samples containing silver, it ranged from 68 to 97%. Only two samples contain aluminum. Although the investigated chasuble is recorded in the inventory as an artifact of the XV century, a part of the yarns is composed of materials attributed to later period. In fact, the voluntary use of aluminum in metal alloys is du…

Voltammetric determination of platinum in perfusate and blood: Preliminary data on pharmacokinetic study of arterial infusion with oxaliplatin

Abstract Because Platinum Group Elements have found widespread use in catalytic converters in cars and as chemotherapeutic agent, interest in the development of reliable analytical methods is carried out in order to monitor these analita in humans to protect the citizen's health. Considering that information on the levels of many trace elements in biological matrices is scarce and for many non-essential elements, baseline levels in the population, and especially in those particularly exposed to the risk are lacking, in this paper we optimize an analytical method for biological matrices, using a voltammetric technique to measure the concentration of Pt in blood and perfusate. The amount of P…

Micro-determination of dithiocarbamates in pesticide formulations using voltammetry

Abstract The purpose of this work was to develop a reliable method for the micro-determination of dithiocarbamates (mancozeb, maneb, propineb, nabam, Na(CH3)2DTC, zineb, ziram, ferbam and thiram) in pesticide formulations for agriculture using adsorptive stripping voltammetry (AdSV). The accuracy of analytical method was valued by analyzing simulate formulation samples prepared by us with known amounts of active ingredients. In addition, the applicability of the AdSV procedure for the analysis of DTCs and EBDTCs in micro-samples was evaluated by estimating its recoveries from spiked commercial formulate samples. The accuracy, valuated as recovery percentage ranged between 85% and 97%. The p…

The determination of mineral acidity excess in solutions containing Ga(III), Al(III), Bi(III)

Abstract A new procedure is proposed to carry out volumetric determinations of the strong acid content of a solution in the presence of inorganic cations such as Ga 3+ , Al 3+ , Bi 3+ which, showing in aqueous solution an acidic behaviour, introduce non negligible interferences in these determinations. Before the acid–base titration, an equivalent amount of a ligand, such as dihydrogen ethylendiamino tetraacetate is added, in order to strongly complex the cation masking it toward the successive addition of a strong base. Interferences are thus removed, and the volumetric determination of the strong acid excess plus the hydrogen ions set free from the ligand, as a consequence of the complex …

The complex formation equilibria between Zn(II) and iminodiacetic acid (IDA) in NaClO4 1 M at 25°C

Profiles and Sources of PAHs in Sediments from an Open-Pit Mining Area in the Peruvian Andes

The Peruvian Andes are one of the most productive areas for mining and therefore also one of the most exposed to these sources of pollution. This article reports the characterization of Polycyclic Aromatic Hydrocarbons (PAHs) in sediments of Cerro de Pasco area (Peru) located close to a large open-pit mine and, in recent years, several reports have provided evidence of environmental contamination and related health problems. Investigations were carried out into the fifteen PAHs identified by the US-Environment Protection Agency (US-EPA) as requiring priority monitoring, other non US-EPA listed PAHs and perylene were also investigated in order to obtain further information on their origins. …

An analytical method for monitoring micro-traces of landfill leachate in groundwater using fluorescence excitation–emission matrix spectroscopy

In this study, we use three-dimensional excitation-emission matrix (EEM) fluorescence spectroscopy for the identification of contamination of natural water bodies by landfill leachate. In particular, EEM was applied to provide information about the presence and quantities of leachate in ground waters. A good linear relationship was found between the fluorescence intensity emission of groundwater spiked with landfill leachate and the volumes of the latter, suggesting that there was no intrinsic fluorescence in the concentration range of 0-1000 μL L-1. The obtained values of the LOD (10 μL L-1; TOC = 34 μg L-1) and LOQ (34 μL L-1; TOC = 114 μg L-1) allow us to detect the presence and the amou…

Platinum and rhodium in potato samples by using voltammetric techniques

Potato is a starchy, tuberous crop from the perennial Solanum tuberosum having high nutritional values. This paper is the first analytical approach to quantify Pt and Rh in vegetal food. In this study a total of 38 different potato samples produced in Europe and one in Australia were investigated. Determinations of Pt and Rh in potato samples were carried out by Differential pulse voltammetry (DPV/a) for platinum and by Adsorptive stripping voltammetry (AdSV) for Rh using standard addition procedure. Because no certified reference potatoes containing platinum and rhodium are available, we used addition standard method. The quantification limits for Pt and Rh are 0.007 and 0.0008 &mu

Voltammetric Analysis of Platinum in Environmental Matrices

This article will summarize measurement data for Pt in different environmental samples obtained by the authors using a recently developed approach by voltammetric analysis. A fast accumulation of platinum and rhodium in the environmental and biological matrices has been observed in the last few years and concern has arisen about potential environmental and health risks. Voltammetry was used for the determination of Pt and Rh in airborne particulate collected in Palermo, Italy. Possible interferences by other environmental metals have also been evaluated. All samples show concentrations of Pt and Rh above average upper crust values. The Pt and Rh concentrations in particulate samples collect…

Il sistema Bismutile-DTPA in NaClO4 3 M a 25°C

A Short Review of Simple Analytical Methods for the Evaluation of PAHs and PAEs as Indoor Pollutants in House Dust Samples

Studies on indoor air quality are indispensable when considering that people spend approximately 85% of their time in confined environments. This short review mostly takes into consideration research that uses passive samplers to evaluate the quality of indoor environments (houses, school, cars, etc.). This short review summarizes most analytical methods to detect and quantify PAHs and PAEs in house dust used as a passive sampler. The objective of house dust analysis is to identify the presence, amount and distribution of specific hazardous substances in confined spaces and, if possible, to identify their sources. Household dust and the compounds present in it can enter the human body by in…

Platinum and rhodium associated with the leaves of Nerium oleander L.; analytical method using voltammetry; assessment of air quality in the Palermo (Italy) area

Abstract A rapid accumulation of the catalytic active noble metals in the environmental and biological matrices was observed and concern arose about potential environmental and health risks. The development of reliable analytic methods to measure very low Pt and Rh concentrations is required. The main purpose of this work was to develop a reliable method for the determination of Pt and Rh in environmental matrices because of inherent difficulties in using conventional techniques used, in particular, the ICP-OES technique. A direct determination of Pt using ICP-MS, for instance, is problematic, due to interfering signals. In this work, differential pulse voltammetry (DPV/a) and adsorptive st…

The Vanadyl-Diethilenetriaminopentaacetate system in aqueous 3 M NaClO4