Abstract On the 5th of May 2008, the first recorded eruption of the Chaiten Volcano in southern C... more Abstract On the 5th of May 2008, the first recorded eruption of the Chaiten Volcano in southern Chile occurred. Because one of the main natural sources of Sb is volcanic activity, it was necessary to study the distribution of Sb and its species in the nearby ecosystem. The present study aims to develop a methodology for total Sb determination by ICP-MS and a method for Sb(V) and Sb(III) determination by HPLC-HG-AFS in soils, sediments and volcanic ash. Microwave digestion in a 6 mL HNO 3 and 0.5 mL HBF 4 acid digestion mixture can achieve total solubilization of Sb in solid samples. Thirty minutes at 200 °C with 100 mmol L − 1 of oxalic acid were suitable conditions for fast and efficient microwave extraction to obtain a good extraction yield. However, Sb(III) stabilization was strongly inhibited; thus, the mixture of 100 mmol L − 1 + 20 mmol L − 1 of ascorbic acid was the best for Sb solubilization and Sb(III) stabilization. A total of 1.8 ± 0.1 μg g − 1 of Sb was quantified in the volcanic ash from the first eruption. The Sb concentrations in the sediments were 3 times higher than the Sb concentrations in the sediments from the reference zone. In the extracts of the volcanic ash and sediment, Sb(III) was the most abundant species, accounting for 70 to 97% of the total Sb found in the extracts. The results suggest that most of the Sb thrown from the Chaiten Volcano accumulated in the sediments at the mouths of the Yelcho and Chaiten Rivers, mainly in the form of Sb(III).
We report here the use of commercial screen-printed disposable sensors comprising a sputtered bis... more We report here the use of commercial screen-printed disposable sensors comprising a sputtered bismuth working electrode, a silver pseudo reference electrode and a carbon auxiliary electrode (whole set referred as BispSPE), as a new and advantageous alternative for reliable and convenient monitoring of Cd and Pb in atmospheric particulate matter (PM10 fraction) by anodic stripping voltammetry after acid digestion. After a detailed exploration of surface composition and depth profiles of the BispSPE by SEM, EDX, XPS and EIS, chemical and instrumental variables have been optimized to develop a reliable method capable of measuring Cd and Pb with detection limits of 11.8 ng mL−1 and 6.1 ng mL−1 respectively. These detection limits are useful for pollution monitoring of these elements in ambient air under the requirements of international health and environmental protection standards. The accuracy of the method was assessed by voltammetric measurements of Cd and Pb in ERM®-CZ120 Fine dust (PM10-like) and ERM® 1648a Urban Particulate Matter certified reference materials. The applicability of the method to Cd and Pb determination in real samples was demonstrated by analysis of PM10 samples from the air quality network in Extremadura, with a good correlation respect to the standard ICP-MS methodology. Our work constitutes the first reference about the use of disposable sensors based on BispSPE for the determination of heavy metals in atmospheric particulate matter samples.
With an estimated present global market of US$ 86.3
billion and expected annual increase around ... more With an estimated present global market of US$ 86.3
billion and expected annual increase around 7.9 % from
now to 2020, sensors are nowadays one of the most active
areas of research and technological developments [1]
and a basic pillar of the emerging mobile health strategy
that is expected to be revolutionizing healthcare in the
near future. The biosensor and chemical sensor category
is one of the most growing segment of this market, mainly
due to increased use for medical purposes. Wearable
electrochemical sensors conform a particularly flourishing
category that benefits from the improvements in micro
and nano fabrication of electrodes and instrumental
components based on a range of new electrode materials
(e.g. graphene). They are also expanding thanks to the
widespread availability of advanced signal processing and
management technologies on smartphones, tablets and
similar portable devices. The aim of this contribution is
to highlight the most outstanding recent progresses in
the field of wearable electrochemical sensors for decentralized
bioanalysis and show some examples of research
trends that will shape the sector and expand applicability
fields in the near future.
The present work investigates soil pollution by elemental contaminants and compares ecological ri... more The present work investigates soil pollution by elemental contaminants and compares ecological risk indexes related to industrial activities for the case study of Puchuncaví-Ventanas: a relevant industrial zone located in central Chile. Selected elements (As, Pb, Cd, Ni, Hg, V, Mn, Zn, Sr, Sb, Cr, Co, Cu, K, and Ba) were analyzed during a long-term period (yearly sampling campaigns during 2007–2011), at 5 sampling stations representing different degrees of impact. PCA and cluster analysis allowed identifying a copper smelter and a coal-fired power plant complex as major pollution sources. Geoaccumulation index (Igeo), enrichment factor (EF), contamination factor (Cf), contamination degree (Cdeg), and integrated pollution index (IPI) are critically discussed for quantitative ecological risk assessment. Igeo, EF and Cf indexes are producing comparable environmental information, showing moderate to high pollution risks in the area that demands further monitoring and adoption of prevention and remediation measures.
A combination of probe ultrasonic extraction, optimized by surface response methodology, and Indu... more A combination of probe ultrasonic extraction, optimized by surface response methodology, and Inductively coupled plasma mass spectrometry (ICP-MS) detection is described in this work as an effective methodology for mercury monitoring in soils affected by industrial emissions. Minute amounts of samples (typically 20 mg) can be extracted in 3 min by 1 mL of HCl-based extracting solution, without risk of mercury losses, and sub sequentially assayed by ICP-MS. The method was successfully tested on soil standard reference materials and then applied to mercury monitoring in a large set of real soil samples collected during a long-term monitoring survey (2007–2011) around the industrial area of Puchuncaví, Chile. The method proved to be useful for investigation of spatial and temporal mercury variability in the area, showing an intermediate to high mercury contamination with potential impact on the surrounding ecosystem.
A combination of probe ultrasonic extraction, optimized by surface response methodology, and Indu... more A combination of probe ultrasonic extraction, optimized by surface response methodology, and Inductively coupled plasma mass spectrometry (ICP-MS) detection is described in this work as an effective methodology for mercury monitoring in soils affected by industrial emissions. Minute amounts of samples (typically 20 mg) can be extracted in 3 min by 1 mL of HCl-based extracting solution, without risk of mercury losses, and sub sequentially assayed by ICP-MS. The method was successfully tested on soil standard reference materials and then applied to mercury monitoring in a large set of real soil samples collected during a long-term monitoring survey (2007–2011) around the industrial area of Puchuncaví, Chile. The method proved to be useful for investigation of spatial and temporal mercury variability in the area, showing an intermediate to high mercury contamination with potential impact on the surrounding ecosystem.
This study presents the results of a quality assurance evaluation program applied to the method r... more This study presents the results of a quality assurance evaluation program applied to the method routinely used for the evaluation of a large elemental profile in aerosol samples from the air quality surveillance network of Extremadura, Spain, where low pollution levels are usually encountered. A critical evaluation of the most relevant analytical steps is presented, including long-term blank values evaluation, limits of detection, certified reference material recoveries, method uncertainty and results of comparison studies for gravimetric and trace element analysis. Results obtained at the air quality network of Extremadura for the gravimetric and multielemental analysis are presented for the 2008 campaign.
A new methodology involving a simple and fast pretreatment of the samples by microwave-assisted e... more A new methodology involving a simple and fast pretreatment of the samples by microwave-assisted extraction and concentration by N2 stream, followed by HPLC with fluorescence detection, was used for determining the concentration of benzo(a)pyrene (BaP) in atmospheric particulate matter (PM10 fraction). Obtained LOD, 1.0 × 10−3 ng/m3, was adequate for the analysis of benzo(a)pyrene in the samples, and BaP recovery from PAH in Fine Dust (PM10-like) certified reference material was nearly quantitative (86 %). The validated procedure was applied for analyzing 115 PM10 samples collected at different sampling locations in the low-polluted area of Extremadura (Southwest Spain) during a monitoring campaign carried out in 2011–2012. BaP spatial variations and seasonal variability were investigated as well as the influence of meteorological conditions and different air pollutants concentrations. A normalized protocol for health risk assessment was applied to estimate lifetime cancer risk due to BaP inhalation in the sampling areas, finding that around eight inhabitants per million people may develop lung cancer due to the exposition to BaP in atmospheric particulates emitted by the investigated sources.
Abstract On the 5th of May 2008, the first recorded eruption of the Chaiten Volcano in southern C... more Abstract On the 5th of May 2008, the first recorded eruption of the Chaiten Volcano in southern Chile occurred. Because one of the main natural sources of Sb is volcanic activity, it was necessary to study the distribution of Sb and its species in the nearby ecosystem. The present study aims to develop a methodology for total Sb determination by ICP-MS and a method for Sb(V) and Sb(III) determination by HPLC-HG-AFS in soils, sediments and volcanic ash. Microwave digestion in a 6 mL HNO 3 and 0.5 mL HBF 4 acid digestion mixture can achieve total solubilization of Sb in solid samples. Thirty minutes at 200 °C with 100 mmol L − 1 of oxalic acid were suitable conditions for fast and efficient microwave extraction to obtain a good extraction yield. However, Sb(III) stabilization was strongly inhibited; thus, the mixture of 100 mmol L − 1 + 20 mmol L − 1 of ascorbic acid was the best for Sb solubilization and Sb(III) stabilization. A total of 1.8 ± 0.1 μg g − 1 of Sb was quantified in the volcanic ash from the first eruption. The Sb concentrations in the sediments were 3 times higher than the Sb concentrations in the sediments from the reference zone. In the extracts of the volcanic ash and sediment, Sb(III) was the most abundant species, accounting for 70 to 97% of the total Sb found in the extracts. The results suggest that most of the Sb thrown from the Chaiten Volcano accumulated in the sediments at the mouths of the Yelcho and Chaiten Rivers, mainly in the form of Sb(III).
We report here the use of commercial screen-printed disposable sensors comprising a sputtered bis... more We report here the use of commercial screen-printed disposable sensors comprising a sputtered bismuth working electrode, a silver pseudo reference electrode and a carbon auxiliary electrode (whole set referred as BispSPE), as a new and advantageous alternative for reliable and convenient monitoring of Cd and Pb in atmospheric particulate matter (PM10 fraction) by anodic stripping voltammetry after acid digestion. After a detailed exploration of surface composition and depth profiles of the BispSPE by SEM, EDX, XPS and EIS, chemical and instrumental variables have been optimized to develop a reliable method capable of measuring Cd and Pb with detection limits of 11.8 ng mL−1 and 6.1 ng mL−1 respectively. These detection limits are useful for pollution monitoring of these elements in ambient air under the requirements of international health and environmental protection standards. The accuracy of the method was assessed by voltammetric measurements of Cd and Pb in ERM®-CZ120 Fine dust (PM10-like) and ERM® 1648a Urban Particulate Matter certified reference materials. The applicability of the method to Cd and Pb determination in real samples was demonstrated by analysis of PM10 samples from the air quality network in Extremadura, with a good correlation respect to the standard ICP-MS methodology. Our work constitutes the first reference about the use of disposable sensors based on BispSPE for the determination of heavy metals in atmospheric particulate matter samples.
With an estimated present global market of US$ 86.3
billion and expected annual increase around ... more With an estimated present global market of US$ 86.3
billion and expected annual increase around 7.9 % from
now to 2020, sensors are nowadays one of the most active
areas of research and technological developments [1]
and a basic pillar of the emerging mobile health strategy
that is expected to be revolutionizing healthcare in the
near future. The biosensor and chemical sensor category
is one of the most growing segment of this market, mainly
due to increased use for medical purposes. Wearable
electrochemical sensors conform a particularly flourishing
category that benefits from the improvements in micro
and nano fabrication of electrodes and instrumental
components based on a range of new electrode materials
(e.g. graphene). They are also expanding thanks to the
widespread availability of advanced signal processing and
management technologies on smartphones, tablets and
similar portable devices. The aim of this contribution is
to highlight the most outstanding recent progresses in
the field of wearable electrochemical sensors for decentralized
bioanalysis and show some examples of research
trends that will shape the sector and expand applicability
fields in the near future.
The present work investigates soil pollution by elemental contaminants and compares ecological ri... more The present work investigates soil pollution by elemental contaminants and compares ecological risk indexes related to industrial activities for the case study of Puchuncaví-Ventanas: a relevant industrial zone located in central Chile. Selected elements (As, Pb, Cd, Ni, Hg, V, Mn, Zn, Sr, Sb, Cr, Co, Cu, K, and Ba) were analyzed during a long-term period (yearly sampling campaigns during 2007–2011), at 5 sampling stations representing different degrees of impact. PCA and cluster analysis allowed identifying a copper smelter and a coal-fired power plant complex as major pollution sources. Geoaccumulation index (Igeo), enrichment factor (EF), contamination factor (Cf), contamination degree (Cdeg), and integrated pollution index (IPI) are critically discussed for quantitative ecological risk assessment. Igeo, EF and Cf indexes are producing comparable environmental information, showing moderate to high pollution risks in the area that demands further monitoring and adoption of prevention and remediation measures.
A combination of probe ultrasonic extraction, optimized by surface response methodology, and Indu... more A combination of probe ultrasonic extraction, optimized by surface response methodology, and Inductively coupled plasma mass spectrometry (ICP-MS) detection is described in this work as an effective methodology for mercury monitoring in soils affected by industrial emissions. Minute amounts of samples (typically 20 mg) can be extracted in 3 min by 1 mL of HCl-based extracting solution, without risk of mercury losses, and sub sequentially assayed by ICP-MS. The method was successfully tested on soil standard reference materials and then applied to mercury monitoring in a large set of real soil samples collected during a long-term monitoring survey (2007–2011) around the industrial area of Puchuncaví, Chile. The method proved to be useful for investigation of spatial and temporal mercury variability in the area, showing an intermediate to high mercury contamination with potential impact on the surrounding ecosystem.
A combination of probe ultrasonic extraction, optimized by surface response methodology, and Indu... more A combination of probe ultrasonic extraction, optimized by surface response methodology, and Inductively coupled plasma mass spectrometry (ICP-MS) detection is described in this work as an effective methodology for mercury monitoring in soils affected by industrial emissions. Minute amounts of samples (typically 20 mg) can be extracted in 3 min by 1 mL of HCl-based extracting solution, without risk of mercury losses, and sub sequentially assayed by ICP-MS. The method was successfully tested on soil standard reference materials and then applied to mercury monitoring in a large set of real soil samples collected during a long-term monitoring survey (2007–2011) around the industrial area of Puchuncaví, Chile. The method proved to be useful for investigation of spatial and temporal mercury variability in the area, showing an intermediate to high mercury contamination with potential impact on the surrounding ecosystem.
This study presents the results of a quality assurance evaluation program applied to the method r... more This study presents the results of a quality assurance evaluation program applied to the method routinely used for the evaluation of a large elemental profile in aerosol samples from the air quality surveillance network of Extremadura, Spain, where low pollution levels are usually encountered. A critical evaluation of the most relevant analytical steps is presented, including long-term blank values evaluation, limits of detection, certified reference material recoveries, method uncertainty and results of comparison studies for gravimetric and trace element analysis. Results obtained at the air quality network of Extremadura for the gravimetric and multielemental analysis are presented for the 2008 campaign.
A new methodology involving a simple and fast pretreatment of the samples by microwave-assisted e... more A new methodology involving a simple and fast pretreatment of the samples by microwave-assisted extraction and concentration by N2 stream, followed by HPLC with fluorescence detection, was used for determining the concentration of benzo(a)pyrene (BaP) in atmospheric particulate matter (PM10 fraction). Obtained LOD, 1.0 × 10−3 ng/m3, was adequate for the analysis of benzo(a)pyrene in the samples, and BaP recovery from PAH in Fine Dust (PM10-like) certified reference material was nearly quantitative (86 %). The validated procedure was applied for analyzing 115 PM10 samples collected at different sampling locations in the low-polluted area of Extremadura (Southwest Spain) during a monitoring campaign carried out in 2011–2012. BaP spatial variations and seasonal variability were investigated as well as the influence of meteorological conditions and different air pollutants concentrations. A normalized protocol for health risk assessment was applied to estimate lifetime cancer risk due to BaP inhalation in the sampling areas, finding that around eight inhabitants per million people may develop lung cancer due to the exposition to BaP in atmospheric particulates emitted by the investigated sources.
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billion and expected annual increase around 7.9 % from
now to 2020, sensors are nowadays one of the most active
areas of research and technological developments [1]
and a basic pillar of the emerging mobile health strategy
that is expected to be revolutionizing healthcare in the
near future. The biosensor and chemical sensor category
is one of the most growing segment of this market, mainly
due to increased use for medical purposes. Wearable
electrochemical sensors conform a particularly flourishing
category that benefits from the improvements in micro
and nano fabrication of electrodes and instrumental
components based on a range of new electrode materials
(e.g. graphene). They are also expanding thanks to the
widespread availability of advanced signal processing and
management technologies on smartphones, tablets and
similar portable devices. The aim of this contribution is
to highlight the most outstanding recent progresses in
the field of wearable electrochemical sensors for decentralized
bioanalysis and show some examples of research
trends that will shape the sector and expand applicability
fields in the near future.
billion and expected annual increase around 7.9 % from
now to 2020, sensors are nowadays one of the most active
areas of research and technological developments [1]
and a basic pillar of the emerging mobile health strategy
that is expected to be revolutionizing healthcare in the
near future. The biosensor and chemical sensor category
is one of the most growing segment of this market, mainly
due to increased use for medical purposes. Wearable
electrochemical sensors conform a particularly flourishing
category that benefits from the improvements in micro
and nano fabrication of electrodes and instrumental
components based on a range of new electrode materials
(e.g. graphene). They are also expanding thanks to the
widespread availability of advanced signal processing and
management technologies on smartphones, tablets and
similar portable devices. The aim of this contribution is
to highlight the most outstanding recent progresses in
the field of wearable electrochemical sensors for decentralized
bioanalysis and show some examples of research
trends that will shape the sector and expand applicability
fields in the near future.