Please use this identifier to cite or link to this item:
|Title:||Metal ion sensor with catalytic DNA in a nanofluidic intelligent processor|
|Authors:||Strategic Environmental Research and Development Program (U.S.)|
Cropek, Donald M. (Donald Michael)
Dalavoy, Tulika S.
Bohn, Paul W.
Sweedler, Johnathan V.
Shannon, Mark A.
|Publisher:||Construction Engineering Research Laboratory (U.S.)|
Engineer Research and Development Center (U.S.)
Abstract: Due to the numerous toxicological effects of lead, its presence in the environment needs to be effectively monitored. Incorporating a biosensing element within a microfluidic platform enables rapid and reliable determinations of lead at trace levels. This work produced a microchip-based lead sensor that employs a lead-specific DNAzyme (also called catalytic DNA or deoxyribozyme) as a recognition element that cleaves its complementary substrate DNA strand only in the presence of cationic lead (Pb2+). Fluorescent tags on the DNAzyme translate the cleavage events to measurable, optical signals proportional to Pb2+ concentration. The DNAzyme responds sensitively and selectively to Pb2+, and immobilizing the DNAzyme in the sensor permits both sensor regeneration and localization of the detection zone. The immobilized DNAzyme retains its Pb2+ detection activity in the microfluidic device and can be regenerated and reused. The particular DNAzyme shows no response to other common metal cations and the presence of these contaminants does not interfere with the lead-induced fluorescence signal. Attempts were made to incorporate a second DNAzyme with selectivity for uranium in the same microfluidic chip sensor, to demonstrate multiplexing capabilities for multiple metal analytes in a single injection. Crosstalk between the lead DNAzyme and the uranium DNAzyme severely limited the utility of this multi-analytic chip.
|Rights:||Approved for public release; distribution is unlimited.|
|Appears in Collections:||Technical Report|
Files in This Item:
|ERDC-CERL-TR-11-47.pdf||8.6 MB||Adobe PDF|