Márcio Milani | FURG - Universidade Federal do Rio Grande (original) (raw)

Papers by Márcio Milani

Research paper thumbnail of Optimisation and application of the voltammetric technique for speciation of chromium in the Patos Lagoon Estuary--Brazil

Environmental monitoring and assessment, 2012

The chemical speciation analysis of chromium in one of the most important South American Estuary ... more The chemical speciation analysis of chromium in one of the most important South American Estuary was performed for the first time. Samples were collected in Patos Lagoon Estuary (Brazil) and were analysed by adsorptive cathodic stripping voltammetry, with the following analytical figures of merit: limit of detection, 0.1 nmol L(-1); precision RSD = 3%, n = 7; linearity, from limit of quantitation up to 20 nmol L(-1); and accuracy of 99.8%, expressed as recovery. No labile chromium forms were identified in samples, beside industries and a city were near the study area. It is pointed out a reverse correlation between total and non-active chromium and salinity, which could be explained by biogeochemical processes.

Research paper thumbnail of Construction and performance of a drop cell for the nephelometric determination of sulfur dioxide

Microchemical Journal, 2003

A nephelometric technique based on a liquid drop is described for the measurement of atmospheric ... more A nephelometric technique based on a liquid drop is described for the measurement of atmospheric sulfur dioxide. A 40-ml drop of barium chloride and hydrogen peroxide solution is suspended in a flowing-air sampling stream. The sulfur (IV) collected is oxidized to sulfur (VI) and finally precipitated as barium sulfate. Nephelometric detection of drop is achieved by an appropriate arrangement consisting of an optical fiber contacting the drop and a photodiode placed at 908 relative to the fiber. The design and characteristics of this drop-based gas sensor system are described. The analytical response, as photocurrent, is proportional to the product of the sampling period and the sulfur dioxide concentration. The detection limit is ca. 1.1 mg m for a 10-min sampling time. The present technique is fairly y3 rapid and simple, uses a small amount of reagent and is set up with low-cost equipment, making this system economically viable. ᮊ

Research paper thumbnail of Colorimetric Determination of Sulfur Dioxide in Air Using a Droplet Collector of Malachite Green Solution

Microchemical Journal, 1999

The measurement of sulfur dioxide in air at the parts-per-billion level is described. The experim... more The measurement of sulfur dioxide in air at the parts-per-billion level is described. The experimental arrangement consists of two optical fibers placed on opposite sides of a liquid droplet of malachite green solution. After light has been passed through the droplet, the transmitted light is ...

Research paper thumbnail of Development and validation of a method using SPE and LC-ESI-MS-MS for the determination of multiple classes of pesticides and metabolites in water samples

Journal of the Brazilian Chemical Society, 2010

Um método analítico baseado na extração em fase sólida e cromatografia líquida acoplada à espectr... more Um método analítico baseado na extração em fase sólida e cromatografia líquida acoplada à espectrometria de massas tandem (LC-ESI-MS-MS) foi desenvolvido e validado para a determinação e confirmação de dezoito agrotóxicos (herbicidas, inseticidas e fungicidas) e dois metabólitos em amostras de água. Os limites de detecção variaram de 0,4 a 40,0 ng L -1 e os limites de quantificação de 4,0 a 100,0 ng L -1 . Foi obtida boa linearidade, com r 2 > 0,99 para todos os compostos. As recuperações, para 95% dos compostos, variaram de 70 a 120%, com RSDs menores que 21% para todos. Através do monitoramento de reações múltiplas (MRM), foram selecionadas duas diferentes transições íon precursor-íon produto para cada agrotóxico. A metodologia proposta pode ser usada para a determinação de resíduos de agrotóxicos em águas de superfície e potável, em concordância com a Lei n° 518 do Ministério da Saúde, Brasil, e com os parâmetros da União Européia para água potável (Directive 98/83/EC).

Research paper thumbnail of Colorimetric determination of formaldehyde in air using a hanging drop of chromotropic acid

Journal of Environmental Monitoring, 2000

A simple and sensitive method to determine parts per billion (ppb) of atmospheric formaldehyde in... more A simple and sensitive method to determine parts per billion (ppb) of atmospheric formaldehyde in situ, using chromotropic acid, is described. A colorimetric sensor, coupled to a droplet of 15.5 microL chromotropic acid, was constructed and used to sample and quantify formaldehyde. The sensor was set up with two optical fibers, a light emitting diode (LED) and two photodiodes. The reference and transmitted light were measured by a photodetection arrangement that converts the signals into units of absorbance. Air was sampled around the chromotropic acid droplet. A purple product was formed and measured after the sampling terminated (typically 7 min). The response is proportional to the sampling period, analyte concentration and sample flow rate. The detection limit is approximately 2 ppb and can be improved by using longer sampling times and/or a sampling flow rate higher than that used in this work, 200 mL min-1. The present technique affords a simple, inexpensive near real-time measurement with very little reagent consumption. The method is selective and highly sensitive. This sensor could be used either for outdoor or indoor atmospheres.

Research paper thumbnail of Development and application of methods using SPE, HPLC-DAD, LC-ESI-MS/MS and GFAAS for the determination of herbicides and metals in surface and drinking water

International Journal of Environmental Analytical Chemistry, 2010

... a * , Márcio Raimundo Milani a , Adriana Demoliner a , Luis Felipe Hax Niencheski b &... more ... a * , Márcio Raimundo Milani a , Adriana Demoliner a , Luis Felipe Hax Niencheski b & Ana Laura Venquiaruti Escarrone c pages 1048-1062. ... The local water supply system gets surface water for treatment from the São Gonçalo Channel (Figure 1) which extends for 62 km. ...

Research paper thumbnail of Zinc causes acute impairment of glutathione metabolism followed by coordinated antioxidant defenses amplification in gills of brown mussels Perna perna

Comparative Biochemistry and Physiology Part C: Toxicology & Pharmacology, 2014

Research paper thumbnail of Evidences of continental groundwater inputs to the shelf zone in Albardão, RS, Brazil

Brazilian Journal of Oceanography, 2008

The southern coastal region of Brazil is highly productive and many of its oceanographic processe... more The southern coastal region of Brazil is highly productive and many of its oceanographic processes are still poorly understood due to a great number of forces, such as the continental input from the Plata River and Patos Lagoon, several distinct oceanic water masses, and a complex contribution from groundwater. The shelf near Albardão is highly rich in dissolved nutrients, particularly in the coastal zone. The narrow sandy barrier that separates the ocean from Mangueira Lagoon has led us to wonder about the possibility of groundwater, and if it might play a role in the productivity of the surrounding area. In order to test this hypothesis, nutrient data from Mirim and Mangueira Lagoons and from Albardão were collected during a rainy period. The present work shows the need to include groundwater transport from Mangueira Lagoon to the coastal zone as one of the main sources for the productivity in that region. However, for such phenomenon to be quantified and better understood, it becomes necessary to use natural isotopes as tracers of the underground input.

Research paper thumbnail of A Flow-Injection-ICP System Sequential Multielemental Analysis with Simultaneously Mercury(II) Preconcentration Step

Analytical Letters, 2003

... Luiz Fabricio Zara,1 Julio Cesar Rocha,2,* Ma´rcio Raimundo Milani,3 Andre ... The main param... more ... Luiz Fabricio Zara,1 Julio Cesar Rocha,2,* Ma´rcio Raimundo Milani,3 Andre ... The main parameters related to ICP operation, such as radio frequency power (950–1750 W ... necessary to separate and preconcentrate them, eliminating interferences from the matrix and concentrating ...

Research paper thumbnail of Measurement of nitrogen dioxide and nitrous acid using gas-permeable liquid core waveguides

Analytica Chimica Acta, 2001

Nitrogen dioxide is an important atmospheric contaminant, classified as a criteria pollutant in t... more Nitrogen dioxide is an important atmospheric contaminant, classified as a criteria pollutant in the United States. It can be sensitively determined by the simple colorimetric Griess–Saltzmann method. This can constitute the basis of an inexpensive sensitive instrument based on gas-permeable liquid core waveguide tubes that allow long path absorbance measurement. Nitrous (HONO) acid is often present in the atmosphere along

Research paper thumbnail of In situ measurement of trace metals in estuarine waters of Patos Lagoon using diffusive gradients in thin films (DGT)

Journal of the Brazilian Chemical Society, 2009

A técnica de gradiente difusivo de membrana (DGT) foi utilizada para determinar metais lábeis in ... more A técnica de gradiente difusivo de membrana (DGT) foi utilizada para determinar metais lábeis in situ durante diferentes condições hidrológicas no estuário da Lagoa dos Patos. As amostras de água foram também analisadas para a fração lábil-Chelex para Cd, Co, Cu, Mn, Ni e Zn usando resina Chelex-100. As concentrações lábeis-DGT de Cd, Cu, Ni e Zn foram mais baixas que a lábil-Chelex, possivelmente devido à ligação do metal coloidal na coluna de resina Chelex. Os resultados do DGT indicaram um decréscimo nas concentrações de todos os elementos, refletindo trocas na especiação dos metais em solução causada pela diminuição da salinidade e associado a mudanças de pH no estuário. Os resultados demonstraram a sensibilidade do DGT para a especiação dos metais e a capacidade do uso da técnica DGT em águas estuarinas altamente dinâmicas para a obtenção de concentrações de metais lábeis integradas ao longo do tempo.

Research paper thumbnail of Optimisation and application of the voltammetric technique for speciation of chromium in the Patos Lagoon Estuary--Brazil

Environmental monitoring and assessment, 2012

The chemical speciation analysis of chromium in one of the most important South American Estuary ... more The chemical speciation analysis of chromium in one of the most important South American Estuary was performed for the first time. Samples were collected in Patos Lagoon Estuary (Brazil) and were analysed by adsorptive cathodic stripping voltammetry, with the following analytical figures of merit: limit of detection, 0.1 nmol L(-1); precision RSD = 3%, n = 7; linearity, from limit of quantitation up to 20 nmol L(-1); and accuracy of 99.8%, expressed as recovery. No labile chromium forms were identified in samples, beside industries and a city were near the study area. It is pointed out a reverse correlation between total and non-active chromium and salinity, which could be explained by biogeochemical processes.

Research paper thumbnail of Construction and performance of a drop cell for the nephelometric determination of sulfur dioxide

Microchemical Journal, 2003

A nephelometric technique based on a liquid drop is described for the measurement of atmospheric ... more A nephelometric technique based on a liquid drop is described for the measurement of atmospheric sulfur dioxide. A 40-ml drop of barium chloride and hydrogen peroxide solution is suspended in a flowing-air sampling stream. The sulfur (IV) collected is oxidized to sulfur (VI) and finally precipitated as barium sulfate. Nephelometric detection of drop is achieved by an appropriate arrangement consisting of an optical fiber contacting the drop and a photodiode placed at 908 relative to the fiber. The design and characteristics of this drop-based gas sensor system are described. The analytical response, as photocurrent, is proportional to the product of the sampling period and the sulfur dioxide concentration. The detection limit is ca. 1.1 mg m for a 10-min sampling time. The present technique is fairly y3 rapid and simple, uses a small amount of reagent and is set up with low-cost equipment, making this system economically viable. ᮊ

Research paper thumbnail of Colorimetric Determination of Sulfur Dioxide in Air Using a Droplet Collector of Malachite Green Solution

Microchemical Journal, 1999

The measurement of sulfur dioxide in air at the parts-per-billion level is described. The experim... more The measurement of sulfur dioxide in air at the parts-per-billion level is described. The experimental arrangement consists of two optical fibers placed on opposite sides of a liquid droplet of malachite green solution. After light has been passed through the droplet, the transmitted light is ...

Research paper thumbnail of Development and validation of a method using SPE and LC-ESI-MS-MS for the determination of multiple classes of pesticides and metabolites in water samples

Journal of the Brazilian Chemical Society, 2010

Um método analítico baseado na extração em fase sólida e cromatografia líquida acoplada à espectr... more Um método analítico baseado na extração em fase sólida e cromatografia líquida acoplada à espectrometria de massas tandem (LC-ESI-MS-MS) foi desenvolvido e validado para a determinação e confirmação de dezoito agrotóxicos (herbicidas, inseticidas e fungicidas) e dois metabólitos em amostras de água. Os limites de detecção variaram de 0,4 a 40,0 ng L -1 e os limites de quantificação de 4,0 a 100,0 ng L -1 . Foi obtida boa linearidade, com r 2 > 0,99 para todos os compostos. As recuperações, para 95% dos compostos, variaram de 70 a 120%, com RSDs menores que 21% para todos. Através do monitoramento de reações múltiplas (MRM), foram selecionadas duas diferentes transições íon precursor-íon produto para cada agrotóxico. A metodologia proposta pode ser usada para a determinação de resíduos de agrotóxicos em águas de superfície e potável, em concordância com a Lei n° 518 do Ministério da Saúde, Brasil, e com os parâmetros da União Européia para água potável (Directive 98/83/EC).

Research paper thumbnail of Colorimetric determination of formaldehyde in air using a hanging drop of chromotropic acid

Journal of Environmental Monitoring, 2000

A simple and sensitive method to determine parts per billion (ppb) of atmospheric formaldehyde in... more A simple and sensitive method to determine parts per billion (ppb) of atmospheric formaldehyde in situ, using chromotropic acid, is described. A colorimetric sensor, coupled to a droplet of 15.5 microL chromotropic acid, was constructed and used to sample and quantify formaldehyde. The sensor was set up with two optical fibers, a light emitting diode (LED) and two photodiodes. The reference and transmitted light were measured by a photodetection arrangement that converts the signals into units of absorbance. Air was sampled around the chromotropic acid droplet. A purple product was formed and measured after the sampling terminated (typically 7 min). The response is proportional to the sampling period, analyte concentration and sample flow rate. The detection limit is approximately 2 ppb and can be improved by using longer sampling times and/or a sampling flow rate higher than that used in this work, 200 mL min-1. The present technique affords a simple, inexpensive near real-time measurement with very little reagent consumption. The method is selective and highly sensitive. This sensor could be used either for outdoor or indoor atmospheres.

Research paper thumbnail of Development and application of methods using SPE, HPLC-DAD, LC-ESI-MS/MS and GFAAS for the determination of herbicides and metals in surface and drinking water

International Journal of Environmental Analytical Chemistry, 2010

... a * , Márcio Raimundo Milani a , Adriana Demoliner a , Luis Felipe Hax Niencheski b &... more ... a * , Márcio Raimundo Milani a , Adriana Demoliner a , Luis Felipe Hax Niencheski b & Ana Laura Venquiaruti Escarrone c pages 1048-1062. ... The local water supply system gets surface water for treatment from the São Gonçalo Channel (Figure 1) which extends for 62 km. ...

Research paper thumbnail of Zinc causes acute impairment of glutathione metabolism followed by coordinated antioxidant defenses amplification in gills of brown mussels Perna perna

Comparative Biochemistry and Physiology Part C: Toxicology & Pharmacology, 2014

Research paper thumbnail of Evidences of continental groundwater inputs to the shelf zone in Albardão, RS, Brazil

Brazilian Journal of Oceanography, 2008

The southern coastal region of Brazil is highly productive and many of its oceanographic processe... more The southern coastal region of Brazil is highly productive and many of its oceanographic processes are still poorly understood due to a great number of forces, such as the continental input from the Plata River and Patos Lagoon, several distinct oceanic water masses, and a complex contribution from groundwater. The shelf near Albardão is highly rich in dissolved nutrients, particularly in the coastal zone. The narrow sandy barrier that separates the ocean from Mangueira Lagoon has led us to wonder about the possibility of groundwater, and if it might play a role in the productivity of the surrounding area. In order to test this hypothesis, nutrient data from Mirim and Mangueira Lagoons and from Albardão were collected during a rainy period. The present work shows the need to include groundwater transport from Mangueira Lagoon to the coastal zone as one of the main sources for the productivity in that region. However, for such phenomenon to be quantified and better understood, it becomes necessary to use natural isotopes as tracers of the underground input.

Research paper thumbnail of A Flow-Injection-ICP System Sequential Multielemental Analysis with Simultaneously Mercury(II) Preconcentration Step

Analytical Letters, 2003

... Luiz Fabricio Zara,1 Julio Cesar Rocha,2,* Ma´rcio Raimundo Milani,3 Andre ... The main param... more ... Luiz Fabricio Zara,1 Julio Cesar Rocha,2,* Ma´rcio Raimundo Milani,3 Andre ... The main parameters related to ICP operation, such as radio frequency power (950–1750 W ... necessary to separate and preconcentrate them, eliminating interferences from the matrix and concentrating ...

Research paper thumbnail of Measurement of nitrogen dioxide and nitrous acid using gas-permeable liquid core waveguides

Analytica Chimica Acta, 2001

Nitrogen dioxide is an important atmospheric contaminant, classified as a criteria pollutant in t... more Nitrogen dioxide is an important atmospheric contaminant, classified as a criteria pollutant in the United States. It can be sensitively determined by the simple colorimetric Griess–Saltzmann method. This can constitute the basis of an inexpensive sensitive instrument based on gas-permeable liquid core waveguide tubes that allow long path absorbance measurement. Nitrous (HONO) acid is often present in the atmosphere along

Research paper thumbnail of In situ measurement of trace metals in estuarine waters of Patos Lagoon using diffusive gradients in thin films (DGT)

Journal of the Brazilian Chemical Society, 2009

A técnica de gradiente difusivo de membrana (DGT) foi utilizada para determinar metais lábeis in ... more A técnica de gradiente difusivo de membrana (DGT) foi utilizada para determinar metais lábeis in situ durante diferentes condições hidrológicas no estuário da Lagoa dos Patos. As amostras de água foram também analisadas para a fração lábil-Chelex para Cd, Co, Cu, Mn, Ni e Zn usando resina Chelex-100. As concentrações lábeis-DGT de Cd, Cu, Ni e Zn foram mais baixas que a lábil-Chelex, possivelmente devido à ligação do metal coloidal na coluna de resina Chelex. Os resultados do DGT indicaram um decréscimo nas concentrações de todos os elementos, refletindo trocas na especiação dos metais em solução causada pela diminuição da salinidade e associado a mudanças de pH no estuário. Os resultados demonstraram a sensibilidade do DGT para a especiação dos metais e a capacidade do uso da técnica DGT em águas estuarinas altamente dinâmicas para a obtenção de concentrações de metais lábeis integradas ao longo do tempo.