Line Scan Methods for Quantitative Analysis of Teeth ...
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Line Scan Methods for Quantitative Analysis of Teeth, Otolith, and Banded Iron by LA-ICP-MS 1 Matt Horton 2 Sonali Gera, 2 Eric Freeburg, 3 Asish R. Basu, 2 Robyn Hannigan 1 CETAC Technologies, 14306 Industrial Rd., Omaha, NE 68144 2 Arkansas State University, Environmental Sciences, PO Box 847, State University AR, 72467 3 Earth and Environmental Sciences, University of Rochester, Rochester, NY 14627 Instrument Parameters (LA-ICP-MS) Laser ablation system - CETAC LSX-213 ¾ Wavelength 213 nm ¾ Energy 4.5 mJ (100%) ¾ Spot Size 200 μm (tooth & BIF) 25 μm (otolith) ¾ Pulse Frequency 10 Hz ¾ Line scan rate (BIF, Tooth, Otoltih) 40, 30, 10 μm/sec ¾ Carrier Gas (Helium) 700 ml/min PerkinElmer ELAN 9000 ICP-MS ¾ Lens Voltage 7.5 v ¾ ICP RF Power 1500 W ¾ Nebulizer Gas Flow 1.03 L/min ¾ Integration Time 10 ms Detector Settings ¾ Analog -1625 v ¾ Pulse 900 v Results ACKNOWLEDGEMENTS The authors would like to thank Alan Koenig (USGS), the Arkansas Biosciences Institute and the members of the Water Rock and Life lab group at Arkansas State University. Conclusion ¾Laser Ablation is an excellent sample introduction technique for generating spatially sensitive, high resolution elemental maps for a variety of sample types. ¾LA-ICP-MS elemental maps constructed using line scan methods enable point by point calibration to be possible, providing a much faster means (compared to maps compiled from single spot analyses) for obtaining sensitive and reliable quantitative concentration data. ¾Using built in triggering and timing features on the LSX-213, mapping of the samples can be fully automated, minimizing user interaction times. ¾Elemental maps generated for the BIF, Otolith, and Tooth samples provide a means for elucidation of elemental zoning and heterogeneity within entire sample matrices. ¾Depending on the number of elements and line scan speeds and distances, data handling and processing can be time consuming. Sample Preparation ¾All samples were mounted on a petrographic slide and thin sectioned using a Buehler IsoMet low speed saw with diamond wafering blades. Subsequent polishing of the otolith sample was performed to enable age determination and to ensure a flat surface. ¾NIST SRM 2781, MACS-1 (USGS), and MAPS-1 (USGS) external calibration standards were used for calibration of the BIF, otolith, and teeth samples respectively. ¾Laser Ablation and ICP-MS parameters were optimized to achieve stable signals for ubiquitous matrix elements while reducing oxides, doubly charged species and other potential interferences. Trace element maps give unique insight to homogeneity, enrichment, and spatial distribution of elements in solid samples. Depending on the sample type, a wealth of additional information can be gained from sample maps beyond what is available from single or multiple spot analyses or single lines/rasters. With the high spatial lateral resolution possible with the technique, LA-ICP-MS data can be used to construct trace element maps with minimal destruction of the sample. The focus of this study was to compile and interpret elemental maps for three distinct sample types. The first sample, banded iron formation (BIF) in shale, shows distinct hematite/quartz layers. Elemental maps of the BIF’s not only reflect the distinct matrix element layers, but also the trace element and REE distribution between the banded Si and Fe mineral phases. This type of information can be used to gain insight about the underlying bedrock composition, as well as the oxygenation and elemental composition of seawater at the time the rock was formed 3.4 Ga. Human teeth were analyzed by LA-ICP-MS and cross-sectional maps were made to assess temporal variations in Pb and to monitor migration of heavy metals from dental amalgam into the teeth. Finally fish otolith elemental abundances were mapped to explore spatial and temporal distribution of trace elements within and across annuli providing deeper insight into environmental life histories. While other solid sampling methods such as SIMS, XRF, and EPMA may provide rival or comparable spatial resolution, LA-ICP-MS is a powerful tool for elucidating the spatial, quantitative distribution of trace elements. Abstract Background ¾Banded Iron Formation - Banded layers consist mostly of Hematite and Chert. - Sample is from the Eastern Indian Archean Craton of Singhbhum and Orissa - BIF age determined by U-Pb dating of zircon grains from a volcanic ash layer immediately beneath the BIF layers. - The age is 3.4 billion years and makes it one of the oldest and largest BIF deposit in the World. ¾Tooth Sample - Molar tooth containing an occlusal filling extracted in 2008 from a 53 year old male ¾Fish Otolith Sample - The otolith sample was extracted from a 9 year old Walleye collected at Devil’s Fork on the Little Red River in Heber Springs, Arkansas. Age, weight, and length were recorded before extraction. Pb Zn Cu Figure 2. LA-ICP-MS elemental distribution maps of fish otolith constructed from Mg/Ca, Ba/Ca, and Sr/Ca ratios. Ratios were generated using quantitative concentration (ppm) data. Figure 3. LA-ICP-MS elemental distribution maps of a molar tooth containing a occlusal filling generated from quantitative concentration (ppm) data for Pb, Zn, and Cu. The molar tooth was collected from a 53 year old male. Figure 1. LA-ICP-MS elemental distribution maps of a 3.4 Ga BIF sample constructed from quantitative concentration data (ppm) for Fe, Si, Cr, Ni, Mg, K, Ca, Ba, Ce, and Na. Fe X Data 3000 4000 5000 6000 7000 Y Data 4000 4500 5000 5500 6000 6500 7000 7500 2e+5 3e+5 4e+5 5e+5 6e+5 Si X Data 3000 4000 5000 6000 7000 Y Data 4000 4500 5000 5500 6000 6500 7000 7500 2e+5 3e+5 4e+5 5e+5 6e+5 7e+5 8e+5 Ni X Data 3000 4000 5000 6000 7000 Y Data 4000 4500 5000 5500 6000 6500 7000 7500 200 300 400 500 Cr X Data 3000 4000 5000 6000 7000 Y Data 4000 4500 5000 5500 6000 6500 7000 7500 100 150 200 250 300 Mg X Data 3000 4000 5000 6000 7000 Y Data 4000 4500 5000 5500 6000 6500 7000 7500 4000 6000 8000 10000 12000 14000 K X Data 3000 4000 5000 6000 7000 Y Data 4000 4500 5000 5500 6000 6500 7000 7500 1000 1500 2000 2500 Ca X Data 3000 4000 5000 6000 7000 Y Data 4000 4500 5000 5500 6000 6500 7000 7500 4000 6000 8000 10000 Ce X Data 3000 4000 5000 6000 7000 Y Data 4000 4500 5000 5500 6000 6500 7000 7500 40 60 80 100 120 140 Ba X Data 3000 4000 5000 6000 7000 Y Data 4000 4500 5000 5500 6000 6500 7000 7500 10 15 20 25 30 35 40 Na X Data 3000 4000 5000 6000 7000 Y Data 4000 4500 5000 5500 6000 6500 7000 7500 1000 1500 2000 2500
Transcript of Line Scan Methods for Quantitative Analysis of Teeth ...
Line Scan Methods for Quantitative Analysis of Teeth, Otolith, and Banded Iron by LA-ICP-MS1Matt Horton 2Sonali Gera, 2Eric Freeburg, 3Asish R. Basu, 2Robyn Hannigan1CETAC Technologies, 14306 Industrial Rd., Omaha, NE 681442Arkansas State University, Environmental Sciences, PO Box 847, State University AR, 724673Earth and Environmental Sciences, University of Rochester, Rochester, NY 14627
Instrument Parameters (LA-ICP-MS)Laser ablation system - CETAC LSX-213 Wavelength 213 nm Energy 4.5 mJ (100%) Spot Size 200 μm (tooth & BIF)
25 μm (otolith)Pulse Frequency 10 Hz Line scan rate (BIF, Tooth, Otoltih) 40, 30, 10 μm/secCarrier Gas (Helium) 700 ml/min
PerkinElmer ELAN 9000 ICP-MSLens Voltage 7.5 vICP RF Power 1500 WNebulizer Gas Flow 1.03 L/minIntegration Time 10 ms Detector SettingsAnalog -1625 vPulse 900 v
Results
ACKNOWLEDGEMENTSThe authors would like to thank Alan Koenig (USGS), the Arkansas Biosciences Institute and the members of the Water Rock and Life lab group at Arkansas State University.
ConclusionLaser Ablation is an excellent sample introduction technique for generating
spatially sensitive, high resolution elemental maps for a variety of sample types.
LA-ICP-MS elemental maps constructed using line scan methods enable point by point calibration to be possible, providing a much faster means (compared to maps compiled from single spot analyses) for obtaining sensitive and reliable quantitative concentration data.
Using built in triggering and timing features on the LSX-213, mapping of the samples can be fully automated, minimizing user interaction times.
Elemental maps generated for the BIF, Otolith, and Tooth samples provide a means for elucidation of elemental zoning and heterogeneity within entire sample matrices.
Depending on the number of elements and line scan speeds and distances, data handling and processing can be time consuming.
Sample Preparation
All samples were mounted on a petrographic slide and thin sectioned using a Buehler IsoMet low speed saw with diamond wafering blades. Subsequent polishing of the otolith sample was performed to enable age determination and to ensure a flat surface.
NIST SRM 2781, MACS-1 (USGS), and MAPS-1 (USGS) external calibration standards were used for calibration of the BIF, otolith, and teeth samples respectively.
Laser Ablation and ICP-MS parameters were optimized to achieve stable signals for ubiquitous matrix elements while reducing oxides, doubly charged species and other potential interferences.
Trace element maps give unique insight to homogeneity, enrichment, and spatial distribution of elements in solid samples. Depending on the sample type, a wealth of additional information can be gained from sample maps beyond what is available from single or multiple spot analyses or single lines/rasters. With the high spatial lateral resolution possible with the technique, LA-ICP-MS data can be used to construct trace element maps with minimal destruction of the sample. The focus of this study was to compile and interpret elemental maps for three distinct sample types. The first sample, banded iron formation (BIF) in shale, shows distinct hematite/quartz layers. Elemental maps of the BIF’s not only reflect the distinct matrix element layers, but also the trace element and REE distribution between the banded Si and Fe mineral phases. This type of information can be used to gain insight about the underlying bedrock composition, as well as the oxygenation and elemental composition of seawater at the time the rock was formed 3.4 Ga. Human teeth were analyzed by LA-ICP-MS and cross-sectional maps were made to assess temporal variations in Pb and to monitor migration of heavy metals from dental amalgam into the teeth. Finally fish otolith elemental abundances were mapped to explore spatial and temporal distribution of trace elements within and across annuli providing deeper insight into environmental life histories. While other solid sampling methods such as SIMS, XRF, and EPMA may provide rival or comparable spatial resolution, LA-ICP-MS is a powerful tool for elucidating the spatial, quantitative distribution of trace elements.
Abstract
BackgroundBanded Iron Formation
- Banded layers consist mostly of Hematite and Chert.
- Sample is from the Eastern Indian Archean Craton of Singhbhum and Orissa
- BIF age determined by U-Pb dating of zircon grains from a volcanic ash layer immediately beneath the BIF layers.
- The age is 3.4 billion years and makes it one of the oldest and largest BIF deposit in the World.
Tooth Sample
- Molar tooth containing an occlusal filling extracted in 2008 from a 53 year old male
Fish Otolith Sample
- The otolith sample was extracted from a 9 year old Walleye collected at Devil’s Fork on the Little Red River in Heber Springs, Arkansas. Age, weight, and length were recorded before extraction.
Pb
Zn
Cu
Figure 2. LA-ICP-MS elemental distribution maps of fish otolith constructed from Mg/Ca, Ba/Ca, and Sr/Ca ratios. Ratios were generated using quantitative concentration (ppm) data.
Figure 3. LA-ICP-MS elemental distribution maps of a molar tooth containing a occlusal filling generated from quantitative concentration (ppm) data for Pb, Zn, and Cu. The molar tooth was collected from a 53 year old male.
Figure 1. LA-ICP-MS elemental distribution maps of a 3.4 Ga BIF sample constructed from quantitative concentration data (ppm) for Fe, Si, Cr, Ni, Mg, K, Ca, Ba, Ce, and Na.
Fe
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Ca
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Ce
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Ba
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Na
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