Concentrations of nutrients and contaminants in rice grain affect human health, specifically through the localization and chemical form of elements. Methods to spatially quantify the concentration and speciation of elements are needed to protect human health and characterize elemental homeostasis in plants. Here, an evaluation was carried out using quantitative synchrotron radiation microprobe X-ray fluorescence (SR-µXRF) imaging by comparing average rice grain concentrations of As, Cu, K, Mn, P, S and Zn measured with rice grain concentrations from acid digestion and ICP-MS analysis for 50 grain samples. Better agreement was found between the two methods for high-
This content will become publicly available on June 8, 2025
Elemental concentration and phase correlation between the macro and micro-elements in Ocimum sanctum (Tulsi) plant leaves using particle induced X-ray emission
We have investigated the concentration and correlation between the macro and micro-elements found in an
herbal plant named Ocimum sanctum (Tulsi) leaf, using Particle-Induced X-ray Emission (PIXE) spectroscopy. The leaf area was analyzed with a 2 MeV scanning proton micro-beam with a spot size of ~ 1 square micrometer. This study is focused on exploring the correlation between the elemental maps generated using X-ray spectra with micro-PIXE. Two types of correlations i.e., elemental, and concentration-phase correlations were examined. The elemental maps are used to find the relation between the spatial distribution of the elements present in the scanned region while the correlation maps help in understanding which phase corresponds to the region of selected concentration ratios. All the elemental concentrations were determined with the detection limits in ng/mg. The analysis of macro-elements showed that the potassium concentration was highest and phosphorus exhibited the lowest concentration whereas iron was found to be highest in the category of trace or microelements. Moreover, broad-beam runs were also performed on the samples to examine the trend for elemental concentrations.
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- NSF-PAR ID:
- 10539027
- Editor(s):
- Ikeda, Tokihiro
- Publisher / Repository:
- Elsevier
- Date Published:
- Journal Name:
- Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms
- Edition / Version:
- NIMB
- Volume:
- 554
- Issue:
- B
- ISSN:
- 0168-583X
- Page Range / eLocation ID:
- 165412
- Subject(s) / Keyword(s):
- PIXE, Ocimum sanctum, X-ray spectroscopy, Elemental concentration, Tulsi
- Format(s):
- Medium: X Size: 9.7 Other: pdf
- Size(s):
- 9.7
- Sponsoring Org:
- National Science Foundation
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Z elements. Regression fits between the two methods allowed quantitative concentration maps of the measured elements. These maps revealed that most elements were concentrated in the bran, although S and Zn permeated into the endosperm. Arsenic was highest in the ovular vascular trace (OVT), with concentrations approaching 100 mg kg−1in the OVT of a grain from a rice plant grown in As-contaminated soil. Quantitative SR-µXRF is a useful approach for comparison across multiple studies but requires careful consideration of sample preparation and beamline characteristics. -
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