Preconcentrating Minicolumn Sensors for Trace Environmental Monitoring
Preconcentrating minicolumn sensors represent an effective approach to achieve a substantial preconcentration factor within a sensing device, enabling very low detection limits as is required for environmental sensing. A selectively sorbent phase collects and concentrates analyte molecules as sample liquid is pumped through the column, ultimately equilibrating the entire sorbent phase with the analyte concentration in the sample. At equilibration, the amount on the column will be proportional to the analyte concentration when working at trace concentrations. We have demonstrated radiometric detection for the detection of radionuclides with this sensor, incorporating scintillating material in the column with the sorbent phase. The pertechnetate form of 99-technetium can be sensed using a mixed column bed containing anion exchange resin and scintillating plastic beads, collecting scintillation light with a pair of photomultiplier (PMT) tubes external to the transparent column body. For hexavalent chromium, we can also collect anions with anion exchange resin. In this case, optical fibers are coupled to the column body to measure the optical absorbance as a function of the amount of hexavalent chromium captured by the column. Both sensors can detect their respective analytes to levels below water standards.
- Research Organization:
- Pacific Northwest National Lab. (PNNL), Richland, WA (United States). Environmental Molecular Sciences Lab. (EMSL)
- Sponsoring Organization:
- USDOE
- DOE Contract Number:
- AC05-76RL01830
- OSTI ID:
- 929205
- Report Number(s):
- PNNL-SA-56116; 24801; KP1302000; TRN: US0804054
- Resource Relation:
- Conference: IEEE Sensors 2007: 6th IEEE Conference on Sensors, 1357-1360
- Country of Publication:
- United States
- Language:
- English
Similar Records
Quantification of Technetium-99 in Complex Groundwater Matrixes using a Radiometric Preconcentrating Minicolumn Sensor in an Equilibration-based Sensing Approach
Radionuclide Sensors for Environmental Monitoring: From Flow Injection Solid-Phase Absorptiometry to Equilibration-Based Preconcentrating Minicolumn Sensors with Radiometric Detection
Related Subjects
37 INORGANIC
ORGANIC
PHYSICAL AND ANALYTICAL CHEMISTRY
38 RADIATION CHEMISTRY, RADIOCHEMISTRY, AND NUCLEAR CHEMISTRY
CONCENTRATORS
SENSORS
ENVIRONMENTAL MATERIALS
MONITORING
ADSORBENTS
CHROMIUM
DETECTION
PERTECHNETATES
TECHNETIUM 99
SENSITIVITY
TRACE AMOUNTS
Environmental Molecular Sciences Laboratory