Dataset Information

Development of a Novel DGT Passive Sampler for Measuring Cs-137 In Situ in Marine Environments.

ABSTRACT: Cs-137 is the most released fission product in the marine environment. It is important to develop a robust in situ technique for its monitoring. The existing diffusive gradients in thin films (DGT) passive sampling techniques for in situ measurement of Cs⁺ have some limitations due to the ion competition and high pH of seawater. A new DGT sampler based on potassium zinc hexacyanoferrate (KZFCN) as a binding layer has been developed and investigated for the measurement of the time-weighted average concentration of Cs-137 in seawater. This binding layer proved a working pH range of 2-12 and an ionic strength of up to 0.75 M. Two types of diffusive gels were tested and agarose gel (AGE) was chosen for the KZFCN-DGT sampler. The measured Cs⁺ diffusion coefficient (1.71 × 10^-5 cm²·s^-1 at 25 °C) in the diffusive gel from seawater was within the expected range published in the literature. The measured concentrations of Cs-137 in seawater obtained by laboratory deployments of the KZFCN-DGT samplers for up to 4 weeks showed good precision (RSD = 13%) and accuracy (relative error = 8.5%) values. The performance test results demonstrated that the KZFCN-DGT sampler is suitable for long-term monitoring of Cs-137 in seawater due to its high capacity and resistance to ion competition and high pH.

SUBMITTER: Elsenbawy A

PROVIDER: S-EPMC10902808 | biostudies-literature | 2024 Feb

REPOSITORIES: biostudies-literature

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Development of a Novel DGT Passive Sampler for Measuring Cs-137 In Situ in Marine Environments.

Elsenbawy Ahmed A Pates Jacqueline M JM Kamel Nariman H M NHM Morsi Tarek T Mekewi Mohammed M El-Gamal Ayman A Moussa Nabawia A NA Zhang Hao H

Analytical chemistry 20240213 8

Cs-137 is the most released fission product in the marine environment. It is important to develop a robust in situ technique for its monitoring. The existing diffusive gradients in thin films (DGT) passive sampling techniques for in situ measurement of Cs<sup>+</sup> have some limitations due to the ion competition and high pH of seawater. A new DGT sampler based on potassium zinc hexacyanoferrate (KZFCN) as a binding layer has been developed and investigated for the measurement of the time-weig ...[more]

PMID: 38350650

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Dataset Information

Development of a Novel DGT Passive Sampler for Measuring Cs-137 In Situ in Marine Environments.

Publications

Development of a Novel DGT Passive Sampler for Measuring Cs-137 In Situ in Marine Environments.

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