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PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
15
pubmed:dateCreated
2006-8-1
pubmed:abstractText
A sensor technique is described that captures analyte species on a preconcentrating minicolumn containing a selective solid-phase sorbent. In this approach, the sample is pumped through the column until the sorbent phase is fully equilibrated with the sample concentration, and the exit concentration equals the inlet concentration. On-column detection of the captured analytes using radiometric and spectroscopic methods is demonstrated. In trace level detection applications, this sensor provides a steady-state signal that is proportional to sample analyte concentration and is reversible. The method is demonstrated for the detection of Tc-99 using anion-exchange beads mixed with scintillating beads and light detection, Sr-90 using SuperLig 620 beads mixed with scintillating beads and light detection; and hexavalent chromium detection using anion-exchange beads with spectroscopic detection. Theory has been developed to describe the signal at equilibration and to describe analyte uptake as a function of volume and concentration, using parameters and concepts from frontal chromatography. It is shown that experimental sensor behavior closely matches theoretical predictions and that effective sensors can be prepared using low plate number columns. This sensor modality has many desirable characteristics for in situ sensors for trace level contaminant long-term monitoring where the use of consumable reagents for sensor regeneration would be undesirable. Initial experiments in groundwater matrixes demonstrated the detection of Tc-99 at drinking water level standards (activity of 0.033 Bq/mL) and detection of hexavalent chromium to levels below drinking water standards of 50 ppb.
pubmed:language
eng
pubmed:journal
pubmed:status
PubMed-not-MEDLINE
pubmed:month
Aug
pubmed:issn
0003-2700
pubmed:author
pubmed:issnType
Print
pubmed:day
1
pubmed:volume
78
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
5480-90
pubmed:year
2006
pubmed:articleTitle
Equilibration-based preconcentrating minicolumn sensors for trace level monitoring of radionuclides and metal ions in water without consumable reagents.
pubmed:affiliation
Pacific Northwest National Laboratory, P.O. Box 999, Richland, Washington 99352, USA.
pubmed:publicationType
Journal Article