University of North Florida
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Stuart Chalk, Ph.D.
Department of Chemistry
University of North Florida
Phone: 1-904-620-1938
Fax: 1-904-620-3535
Email: schalk@unf.edu
Website: @unf

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Maximo Gallignani

Abbrev:
Gallignani, M.
Other Names:
Address:
Venezuelan Andean Institute for Chemical Research, Faculty of Sciences, Los Andes University, P.O. Box 542, Merida 5101-A, Venezuela
Phone:
+58-74-401375
Fax:
+58-74-401286
Email:
maximo@ula.ve

Citations 8

"A Simple Strategy For Determining Ethanol In All Types Of Alcoholic Beverages Based On Its On-line Liquid-liquid Extraction With Chloroform, Using A Flow Injection System And Fourier Transform Infrared Spectrometric Detection In The Mid-IR"
Talanta 2005 Volume 68, Issue 2 Pages 470-479
Máximo GallignaniCorresponding Author Contact Information, E-mail The Corresponding Author, E-mail The Corresponding Author, Carlos Ayala, Maria del Rosario Brunetto, Jose Luis Burguera and Marcela Burguera

Abstract: In this work, a simple strategy for the determination of ethanol in all types of alcoholic beverages using Fourier transform infrared spectrometric detection has been developed. The methodological proposal includes the quantitative on-line liquid-liquid extraction of ethanol with chloroform, through a sandwich type cell equipped with a PTFE membrane, using a two-channel manifold; and direct measurement of the analyte in the organic phase, by means of Fourier transform infrared spectrometry. The quantification was carried out measuring the ethanol absorbance at 877 cm-1, corrected by means of a baseline established between 844 and 929 cm-1. The procedure, which does not require any sample pretreatment (except for the simple degassing of beer and gassy wine samples, and a simple dilution of spirits with water), was applied to determine ethanol in different alcoholic beverages such as beers, wines and spirits. The results obtained highly agree with those obtained by a derivative FTIR spectrometric procedure, and by head space-gas chromatography with FID detection. The proposed method is simple, fast, precise and accurate. Moreover, it can be easily adapted to any infrared spectrometer equipped with a standard transmission IR cell, and provides attractive analytical features, which are comparable to, or better than those offered by other published methods. In consequence, it represents a valid alternative for the determination of ethanol in alcoholic beverages, and could be suitable for the routine control analysis. © 2005 Elsevier B.V. All rights reserved.

"Flow Analysis-vapor Phase Generation-Fourier Transform Infrared (FA-VPG-FTIR) Spectrometric Determination Of Nitrite"
Talanta 2004 Volume 64, Issue 5 Pages 1290-1298
Máximo Gallignani, Maribel Valero, Carlos Ayala, Maria del Rosario Brunetto, Argenis Sánchez, Jose Luis Burguera and Marcela Burguera

Abstract: In this work, the coupling between flow analysis (FA)-vapor phase generation (VPG) and Fourier transform infrared spectrometry (FTIR) has been proposed as a novel and alternative strategy for the determination of nitrite. The analyte was transformed into the gaseous nitric oxide (NO) by on-line reaction with potassium iodide (KI) or ascorbic acid in acidic medium. The gaseous NO generated was transported by means of a N2 gas carrier stream inside the IR gas cell and the corresponding FTIR spectrum was acquired in a continuous mode. The absorbance at 1876 cm-1, corrected by a baseline established between 1879 and 1872 cm-1 at a nominal resolution of 2 cm-1, was selected as a measurement criterion. The effect of different spectroscopic and flow analysis experimental parameters, such as nominal resolution, number of scans, reducing agent and its concentration, acidic medium, reagents and sample flow rates, and the carrier gas flow rate on the analytical signal, and then in the figures of merit were initially evaluated by using a standard short path length (10 cm) IR gas cell. The optimization of the system was carried out by the univariate method. The main aims of this study were: (i) to investigate the on-line generation of gaseous nitric oxide in a continuous flow system, and (ii) the use of Fourier transform infrared spectrometry as an alternative and selective detector for the determination of nitrite. The proposed method was initially tested and applied for the determination of nitrite in samples with very high concentration of nitrite, such as frankfurters.

"Infrared Detection In Flow Analysis -- Developments And Trends (review)"
Talanta 2004 Volume 64, Issue 5 Pages 1127-1146
Maximo Gallignani and Maria del Rosario Brunetto

Abstract: Flow analysis offers an inexpensive and versatile means for the automation of analytical procedures and hence it has been incorporated in many different techniques. However, the use of infrared detection in flow analysis systems is not common. Whereas Fourier transform infrared (FTIR) spectroscopic detection has been routinely used in gas chromatography (GC), its use for liquid chromatography, and now for flow analysis, flow injection analysis, or sequential injection analysis, is not frequent. The most prominent reasons are probably: (i) the strong absorption of most of the common solvents, specially water, (ii) the relative poor sensibility compared to UV-vis, fluorescence, etc. (iii) FTIR is normally not even considered a valuable detection technique, (iv) problems arising from obtaining adequate information from transient IR signals from the injected samples, and (v) only a few analytical chemist uses routinely the FTIR technique. This practice neglects that IR spectroscopy offers some unique features that now, using modern FTIR instrumentation, can be exploited in an advantageous manner. It is important to realize that each sample (analyte/matrix) represents a special and unique analytical problem; which defines the mode of operation and implementation of the IR technique. Flow analysis-IR techniques - as well as all techniques - has a number of shortcomings to solve these problems. In this article, most of these strategies such as the use of: baseline correction, derivative spectroscopy, stopped flow systems, reverse flow systems, multiparametric calibrations, etc., will be discussed. Additionally, recent developments in on-line gas phase generation-FTIR and hydride generation-FTIR spectrometry, as well as the principles of the HPLC-FTIR and capillary electrophoresis-FTIR hyphenation are also discussed. This review aims to provide an account of the state of the art, of these relatively new techniques. Its beginning, developments, applications and new trends, basically in the MID-IR, and by using transmission cells.

"Flow Analysis-hydride Generation-Fourier Transform Infrared Spectrometric Determination Of Antimony In Pharmaceuticals"
Talanta 2003 Volume 59, Issue 5 Pages 923-934
M. Gallignani, C. Ayala, M. R. Brunetto, M. Burguera and J. L. Burguera

Abstract: In this work, a flow analysis system with hydride generation and Fourier transform infrared (FTIR) spectrometric detection has been developed for the determination of antimony in pharmaceuticals. The method is based on the on-line mineralization/oxidation of the organic antimonials present in the sample and pre-reduction of Sb(V) to Sb(III) with K2S2O8 and KI, respectively; prior to the stibine generation. The gaseous SbH3 is separated from the solution in a gas phase separator, and transported by means of a nitrogen carrier into a short pathway (10 cm) IR gas cell, where the corresponding FTIR spectrum is acquired by accumulating 3 scans in a continuous mode. The 1893 cm-1 band was used for the quantification of the antimony. The procedure is carried out in a closed system, which reduces sample handling and makes possible the complete automation of the antimony determination. The figures of merit of the proposed method (linear range: 0-600 mg l-1, limit of detection (3s)=0.9 mg l-1, limit of quantification (10s)=3 mg Sb l-1, precision (RSD) less than 1% and sample FREQUENCY=28 h-1), are appropriate for the designed application. Furthermore, precise and accurate results were found for the analysis of different antimonial pharmaceutical samples, indicating that the methodology developed represents a valid alternative for the determination of antimony in pharmaceuticals, which could be suitable for the routine control analysis.

"Sequential Determination Of Se(IV) And Se(VI) By Flow Injection-hydride Generation-atomic Absorption Spectrometry With HCl/HBr Microwave Aided Pre-reduction Of Se(VI) To Se(IV)"
Talanta 2000 Volume 52, Issue 6 Pages 1015-1024
M. Gallignani, M. Valero, M. R. Brunetto, J. L. Burguera, M. Burguera and Y. Petit de Peña

Abstract: In this study a flow injection (FI) system used in conjunction with hydride generation (HG), atomic absorption spectrometry (AAS) and microwave (MW) aided pre-reduction of selenite (Se(IV)) to selenate (Se(IV)) with HCl:HBr has been developed in order to differentiate both inorganic selenium species. As full control of the MW reduction step is possible, the experimental approach allows the use of milder acidic conditions (10% v/v of HCl and HBr) than those conventionally accomplished with hydrochloric acid alone (greater than or equal to 50% v/v). Experimental parameters were optimized by the univariate optimization method. Tn either case, the linear range was from 1.0 to 30 µg 1-1. The detection limits based on 30 of the blank signal were 0.25 µg L-1 for Se(IV) and 0.30 µg L-1 for Se(VI). The reproducibility, about 3% RSD and recoveries of different amounts of Se(VI) and Se(IV) added to water and orange juice samples (97-103%) were good. The main advantage of the proposed method is that the sequential determination of Se(IV) and Se(VI) is performed at a high sampling frequency (ca. 50 samples per h) in a closed system without Se losses, and with a minimum sample waste, operator attention, and sample manipulation.
Speciation

"On-line Gaseous Phase Generation - Fourier Transform Infrared (FT-IR) Spectrometry. A New And Powerful Analytical Technique"
Rev. Tec. Ing. Univ. Zulia 2005 Volume 28, Issue 1 Pages 3-27
Máximo Gallignani*, Maribel Valero, Maria del Rosario Brunetto y Carlos Ayala

Abstract: In this work; a critical review about on-line gaseous phases generation with Fourier transform infrared (FTIR) spectrometry detection is presented. In this sense, different experimental approaches for the determination of ethanol and carbonates in different samples, and for the simultaneous determination of benzene, toluene and methyl tert-butyl ether in gasoline; and butyl acetate, toluene and methyl ethyl ketone in commercial paint solvents has been examined. In all these methods, the figures of merit are adequate for the proposed applications, and the results are in good agreement with those obtained by diverse reference procedures. Also, it is presented the recent development of the flow analysis-hydride generation-FTIR coupling for the individual and simultaneous determination of antimony, arsenic and tin, as well as some applications proposed for this technique. All this procedures are focused to demonstrate the real analytic potentiality depicted by the on line gaseous phase generation-FTIR spectrometry technique for the analysis of real samples.

"A Time-based Flow Injection-cold Vapor-atomic Absorption Spectrometry System With Online Microwave Sample Pre-treatment For The Determination Of Inorganic And Total Mercury In Urine"
Anal. Chim. Acta 1998 Volume 369, Issue 1-2 Pages 57-67
M. Gallignani*, H. Bahsas, M. R. Brunetto, M. Burguera, J. L. Burguera and Y. Petit de Peña

Abstract: A time based injection system used in conjunction with cold vapor generation atomic absorption spectrometry and microwave-aided heating oxidation with potassium persulfate has been developed for the determination of total and inorganic mercury in urine samples. Inorganic mercury is determined after reduction with SnCl2 while total mercury is determined after an online oxidation step with persulfate prior to the reduction step to elemental mercury with SnCl2. The difference between total and inorganic mercury determines the organomercury content in samples. Experimental parameters were optimized by the univariate optimization method. A linear calibration graph was obtained in the range 0.2-20 µg L-1 of Hg2+ by using injection times from 0 to 12 s of a solution of 20 µg L-1 of either inorganic or organic mercury. The detection limit based on 3s of the blank signal was 0.1 µg Hg L-1 regardless of the mercury species under evaluation. The relative standard deviations for five independent measurements were 1.5% and 1.0% for total and inorganic mercury. The recoveries of different amounts of inorganic and organic mercury added to urine samples ranged from 98.5% to 102.2% and from 97.0% to 103%, respectively. Good agreement with certified values of the total mercury containing urine reference materials were also obtained. With the proposed procedure, 20 urine samples of unexposed subjects from Merida city were measured; and the values lay in the range between 1.8 and 6.7 µg l-1. In addition, the use of a mercury standard solution as the carrier converts the flow injection manifold used in this work to an online standard addition system which permits a rapid and simple test for monitoring the mercury levels in these samples.
Mercury(II) Mercury Urine Spectrophotometry Sample preparation Timed injection Speciation Optimization Reference material Microwave Online digestion Standard additions calibration

"Flow Analysis-hydride Generation-Fourier Transform Infrared Spectrometry. A New Analytical Technique For The Simultaneous Determination Of Antimony, Arsenic And Tin"
Analyst 2002 Volume 127, Issue 12 Pages 1705-1712
Máximo Gallignani, Carlos Ayala, Rosario Brunetto, Jose Luis Burguera and Marcela Burguera

Abstract: The combination of flow analysis (FA), hydride generation (HG) and Fourier transform infrared ( FTIR) spectrometry is proposed as a novel and powerful analytical technique for the individual and simultaneous determination of antimony, arsenic and tin in aqueous samples. The analytes were transformed into the volatile hydride form by on-line reaction with sodium tetrahydroborate in acidic medium. The gaseous analyte hydrides [MnHm(g)] generated, were transported by means of a carrier gas stream inside the IR gas cell and the corresponding FTIR spectrum was acquired in a continuous mode. The 1893, 1904 and 2115 cm-1 bands of the SbH3, SnH4, and AsH3 were selected for the determination of antimony, tin and arsenic, respectively. The limit of detection (3s) obtained by using a short-path (10 cm) IR gas cell were 0.25, 0.30 and 1.2 mg L-1 for the determination of antimony, tin and arsenic, respectively; while the precision ( relative standard deviation, RSD, n = 5) found from a standard solution containing 50 mg L-1 of each element was, in all cases, less than 0.3%. However, the use of a long-path (7.25 m) IR gas cell improved the figures of merit (sensitivity, limits of detection and quantification) nearly 60-fold. The effect of the main experimental and instrumental variables, such as acidic media, sodium tetraborohydrate concentration, nitrogen flow rate, nominal resolution and the scan accumulation on the analytical signals of the antimony, tin and arsenic hydrides, were studied. Further, the potential of the proposed technique for the simultaneous determination of these elements was tested, analyzing synthetic samples containing different amounts of Sb, Sn and As.