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1.
Ann Chim ; 97(3-4): 141-51, 2007.
Article in English | MEDLINE | ID: mdl-17822223

ABSTRACT

An analytical procedure fit for the simultaneous determination of copper (II), chromium(VI), thallium(I), lead(II), tin(II), antimony(III), and zinc(II) by square wave anodic stripping voltammetry (SWASV) in three interdependent environmental matrices involved in foods and food chain as meals, cereal plants and soils is described. The digestion of each matrix was carried out using a concentrated HCl-HNO3-H2SO4 (meals and cereal plants) and HCl-HNO3 (soils) acidic attack mixtures. 0.1 mol/L dibasic ammonium citrate pH 8.5 was employed as the supporting electrolyte. The voltammetric measurements were carried out using, as working electrode, a stationary hanging mercury drop electrode (HMDE) and a platinum electrode and an Ag/AgCl/KClsat electrode as auxiliary and reference electrodes, respectively. The analytical procedure was verified by the analyses of the standard reference materials: Wholemeal BCR-CRM 189, Tomato Leaves NIST-SRM 1573a and Montana Soil Moderately Elevated Traces NIST-SRM 2711. For all the elements in the certified matrix, the precision as repeatability, expressed as relative standard deviation (Sr %) was lower than 5%. The accuracy, expressed as percentage relative error (e %) was of the order of 3-7%, while the detection limits were in the range 0.015-0.103 microg/g. Once set up on the standard reference materials, the analytical procedure was transferred and applied to commercial meal samples, cereal plants and soils samples drawn in sites devoted to agricultural practice. A critical comparison with spectroscopic measurements is also discussed.


Subject(s)
Electrochemistry/methods , Food Analysis , Metals, Heavy/analysis , Soil/analysis , Edible Grain/chemistry , Electrochemistry/standards , Food Chain , Spectrophotometry, Atomic/standards
2.
Ann Chim ; 96(7-8): 493-504, 2006.
Article in English | MEDLINE | ID: mdl-16948438

ABSTRACT

Analytical results are reported for the determination of inorganic species in water and sediments sampled in the Senio river ecosystem. The species determined are Cu, Pb, Cd, Zn, Co, Cr, Ni, Fe, Mn, Hg, F-, Cl-, Br, NO3-, SO4-, Na+, K+, Ca++, Mg++, NH4+ in integrated water, and Cu, Pb, Cd, Zn, Co, Cr, Ni, Fe, Mn, Hg in sediments. For all the elements, in addition to detection limits, precision and accuracy are given: the former, expressed as relative standard deviation (sr), and the latter, expressed as relative error (e), were good, being in all cases lower than 6%. Limitedly to Cu, Pb, Cd and Zn a critical comparison with voltammetric measurements is also discussed.


Subject(s)
Ecosystem , Environmental Monitoring/methods , Geologic Sediments/analysis , Inorganic Chemicals/analysis , Rivers/chemistry , Water Pollutants, Chemical/analysis , Water/analysis , Electrochemistry/methods , Geologic Sediments/chemistry , Italy , Metals/analysis , Sensitivity and Specificity , Spectrophotometry, Atomic/methods , Trace Elements/analysis , Water/chemistry
3.
Anal Bioanal Chem ; 382(7): 1567-73, 2005 Aug.
Article in English | MEDLINE | ID: mdl-15999268

ABSTRACT

This paper reports voltammetric sequential determination of Pt(II), Pd(II), and Rh(III), by square-wave adsorption stripping voltammetry (SWAdSV), and Pb(II), by square-wave anodic stripping voltammetry (SWASV), in vegetable environmental matrices. Analytical procedures were verified by the analysis of the standard reference materials: Olive Leaves BCR-CRM 062 and Tomato Leaves NIST-SRM 1573a. Precision and accuracy, expressed as relative standard deviation and relative error, respectively, were always less than 6% and the limits of detection (LOD) for each element were below 0.096 mug g(-1). Once set up on the standard reference materials, the analytical procedure was transferred and applied to laurel leaves sampled in proximity to a superhighway and in the Po river mouth area. A critical comparison with spectroscopic measurements is discussed.


Subject(s)
Biosensing Techniques/methods , Environmental Pollutants/analysis , Lead/analysis , Palladium/analysis , Platinum/analysis , Rhodium/analysis , Vegetables/chemistry , Biosensing Techniques/instrumentation , Calibration , Electrochemistry , Environmental Monitoring/instrumentation , Environmental Monitoring/methods , Reference Standards , Sensitivity and Specificity , Spectrophotometry, Atomic
4.
Ann Chim ; 94(3): 197-206, 2004 Mar.
Article in English | MEDLINE | ID: mdl-15206841

ABSTRACT

Membraneless hyperlayer flow field-flow fractionation (Hyp FIFFF) has shown improved performance with respect to Hyp FIFFF with membrane. The conditions for high recovery and recovery independent of sample loading in membraneless Hyp FIFFF have been previously determined. The effect of sample loading should be also investigated in order to optimize the form of the peaks for real samples. The effect of sample loading on peak retention parameters is of prime importance in applications such as the conversion of peaks into particle size distributions. In this paper, a systematic experimental work is performed in order to study the effect of sample loading on retention parameters. A procedure to regenerate the frit operating as accumulation wall is described. High reproducibility is obtained with low system conditioning time.


Subject(s)
Chemistry Techniques, Analytical/methods , Calibration , Filtration , Particle Size , Reproducibility of Results , Specimen Handling
5.
Ann Chim ; 93(1-2): 77-87, 2003.
Article in English | MEDLINE | ID: mdl-12650576

ABSTRACT

Analytical results are reported for the determination of inorganic species in water and sediments sampled in the Lamone and Marzeno rivers ecosystem. The species determined are Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb, Zn, Hg, F-, Cl- Br-, NO3-, SO4--, Na+, K+, Mg++, Ca++, NH4+ in superficial water, and Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb, Zn, Hg in sediments. For all the elements, in addition to detection limits, precision and accuracy are given: the former, expressed as relative standard deviation (s(r)), and the latter, expressed as relative error (e), were good, being in all cases lower than 6%.


Subject(s)
Geologic Sediments/chemistry , Metals/analysis , Water Supply , Ecosystem , Inorganic Chemicals/analysis , Italy
6.
Anal Chem ; 75(23): 6469-77, 2003 Dec 01.
Article in English | MEDLINE | ID: mdl-16465697

ABSTRACT

Characterization of dispersed samples is an outstanding trend in analytical science. Among flow-assisted separation techniques for dispersed samples, size exclusion chromatography, hydrodynamic chromatography, and field-flow fractionation are the most widely applied. With dispersed analytes separated by these techniques, the UV/vis spectrophotometric detectors work as turbidimeters. To directly convert the analytical signal for quantitative analysis, the extinction properties of the dispersed analyte must be known. A new method is proposed to experimentally obtain-by single-run, flow-assisted separation with UV/vis diode-array detectors-the mass-size (or number-size) distribution function of the analytes when a retention-to-size relationship is either theoretically or empirically available for the chosen separation technique. This approach needs neither standards nor reliance on a method to predict the optical properties of the analytes. Theory and original algorithms are presented. Algorithms are then tested to optimize the numerical routines. Accuracy and robustness of the method are evaluated by simulation, and limitations for the application to experimental data are described. Finally, first application to field-flow fractionation shows validity of the method when applied to a few real cases.

7.
Ann Chim ; 92(9): 855-67, 2002 Sep.
Article in English | MEDLINE | ID: mdl-12407908

ABSTRACT

Analytical results are reported for the determination of inorganic species in water and sediments sampled in the Aso river ecosystem. The species determined are Cd, Co, Cr, Cu, Fe, Mn, Ni, Zn, Hg, F-, NO3-, SO4--, Na, K, Ca, Mg, NH4+ in water, and Cd, Co, Cr, Cu, Fe, Mn, Ni, Zn, Hg in sediments. For all the elements, in addition to detection limits, precision and accuracy are given: the former, expressed as relative standard deviation (Sr), and the latter, expressed as relative error (e), were good, being in all cases lower than 6%.


Subject(s)
Fresh Water/chemistry , Geologic Sediments/chemistry , Inorganic Chemicals/analysis , Water Pollutants, Chemical/analysis , Italy , Spectrophotometry, Atomic
8.
Ann Chim ; 92(4): 435-41, 2002 Apr.
Article in English | MEDLINE | ID: mdl-12073889

ABSTRACT

Analytical results are reported for the determination of inorganic species in water and sediments sampled in the Tronto river ecosystem. The species determined are Cd, Co, Cr, Cu, Fe, Mn, Ni, Zn, Hg, F, NO3-, SO4-, Na, K, Ca, Mg, NH4+ in integrated water, and Cd, Co, Cr, Cu, Fe, Mn, Ni, Zn, Hg in sediments. For all the elements, in addition to detection limits, precision and accuracy are given: the former, expressed as relative standard deviation (Sr), and the latter, expressed as relative error (e), were good, being in all cases lower than 5%.


Subject(s)
Metals, Heavy/analysis , Trace Elements/analysis , Water Pollutants/analysis , Ecosystem , Geologic Sediments/chemistry , Italy , Reference Values
9.
Environ Monit Assess ; 75(3): 281-92, 2002 May.
Article in English | MEDLINE | ID: mdl-12004981

ABSTRACT

Arsenic(III), selenium(IV), copper(II), lead(II), cadmium(II), zinc(II) have been determined in sea water, sediments, algae and clams by differential pulse cathodic (DPCSV) and anodic (DPASV) stripping voltammetry. The voltammetric measurements are carried out using a conventional three-electrode cell and the ammonia-ammonium chloride buffer pH 9.2 as supporting electrolyte. The analytical procedure has been verified by the analysis of the standard reference materials (Estuarine Sediment BCR- CRM 277, Ulva Lactuca BCR-CRM 279 and Mussel Tissue BCR-CRM 278). The precision and the accuracy are less than 5%. This procedure is utilized for the monitoring of heavy metals in the Po river mouth area (Italy).


Subject(s)
Bivalvia/chemistry , Environmental Monitoring/methods , Eukaryota/chemistry , Geologic Sediments/chemistry , Metals, Heavy/analysis , Water Pollutants/analysis , Animals , Electrochemistry , Reference Values
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