TNT detection using multiplexed liquid array displacement immunoassays.
The presence of trace contamination of soil and groundwater with explosives is an ongoing concern, for which improved methods are required to facilitate their detection and quantification. This is true both for the monitoring of remediation and for site characterization. Immunosensors have been found effective for solution-phase detection of environmental contaminants. Our work utilized the Luminex100 (flow cytometer) to detect TNT in a multiplexed displacement immunoassay format. The Luminex100 can perform a multiplexed assay by discriminating between up to 100 different bead sets. We used this capability to evaluate four different TNT monoclonal antibodies, two recombinant TNT antibodies, and a control antibody simultaneously for the rapid detection of TNT and other nitroaromatics. TNT could be detected at 0.1 ppb and quantified over the range of 1.0 ppb to 10 ppm. In addition, the assay was shown to be effective in various matrixes such as lake water, seawater, and acetone extracts of soil. Seawater required dilution with two parts buffer to avoid loss of microspheres, while the acetone extracts were diluted 100-fold or more to minimize solvent affects.
Center for Bio/Molecular Science and Engineering, Naval Research Laboratory, Washington, DC 20375, USA. ganderson@cbmse.nrl.navy.mil
George P
GP
Anderson
Solimar C
SC
Moreira
Paul T
PT
Charles
Igor L
IL
Medintz
Ellen R
ER
Goldman
Mazyar
M
Zeinali
Chris R
CR
Taitt
D000911:Antibodies, Monoclonal / Q000276:immunology; D000918:Antibody Specificity; D000937:Antigen-Antibody Reactions; D015374:Biosensing Techniques; D053834:Explosive Agents / Q000032:analysis*; D005434:Flow Cytometry; D007118:Immunoassay / Q000379:methods*; D012623:Seawater / Q000032:analysis / Q000737:chemistry; D012680:Sensitivity and Specificity; D012989:Soil Pollutants / Q000032:analysis*; D012997:Solvents / Q000737:chemistry; D014303:Trinitrotoluene / Q000032:analysis*; D014873:Water Pollutants / Q000032:analysis*
D000911:Antibodies, Monoclonal; D053834:Explosive Agents; D012989:Soil Pollutants; D012997:Solvents; D014873:Water Pollutants; D014303:Trinitrotoluene