Miniaturized lead sensor based on lead-specific DNAzyme in a manocapillary interconnected microfluidic device

被引:97
作者
Chang, IH
Tulock, JJ
Liu, JW
Kim, WS
Cannon, DM
Lu, Y
Bohn, PW
Sweedler, JV
Cropek, DM [1 ]
机构
[1] USA, Engineer Res & Dev Ctr, Construct Engn Res Lab, Champaign, IL 61822 USA
[2] Univ Illinois, Dept Chem, Urbana, IL 61801 USA
[3] Univ Illinois, Beckman Inst Adv Sci & Technol, Urbana, IL 61801 USA
关键词
D O I
10.1021/es040505f
中图分类号
X [环境科学、安全科学];
学科分类号
08 ; 0830 ;
摘要
A miniaturized lead sensor has been developed by combining a lead-specific DNAzyme with a microfabricated device containing a network of microfluidic channels that are fluidically coupled via a nanocapillary array interconnect. A DNAzyme construct, selective for cleavage in the presence of Pb2+ and derivatized with fluorophore (quencher) at the 5' (3') end of the substrate and enzyme strands, respectively, forms a molecular beacon that is used as the recognition element. The nanocapillary array membrane interconnect is used to manipulate fluid flows and deliver the small-volume sample to the beacon in a spatially confined detection window where the DNAzyme is interrogated using laser-induced fluorescence detection. A transformed log plot of the fluorescent signal exhibits a linear response (r(2) = 0.982) over a Pb2+ concentration range of 0.1-100 mu M, and a detection limit of 11 nM. The sensor has been applied to the determination of Pb2+ in an electroplating sludge reference material, the result agreeing with the certified value within 4.9 %. Quantitative measurement of Pb2+ in this complex sample demonstrates the selectivity of this sensor scheme and points favorably to the application of such technologies to analysis of environmental samples. The unique combination of a DNAzyme with a microfluidic-nanofluiclic hybrid device makes it possible to change the DNAzyme to select for other compounds of interest, and to incorporate multiple sensing systems within a single device for greater flexibility. This work represents the initial steps toward creation of a robust field sensor for lead in groundwater or drinking water.
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页码:3756 / 3761
页数:6
相关论文
共 39 条
[1]   Amperometric biosensor based on denatured DNA for the study of heavy metals complexing with DNA and their determination in biological, water and food samples [J].
Babkina, SS ;
Ulakhovich, NA .
BIOELECTROCHEMISTRY, 2004, 63 (1-2) :261-265
[2]   Antibody-based sensors for heavy metal ions [J].
Blake, DA ;
Jones, RM ;
Blake, RC ;
Pavlov, AR ;
Darwish, IA ;
Yu, HN .
BIOSENSORS & BIOELECTRONICS, 2001, 16 (9-12) :799-809
[3]   Nanocapillary array interconnects for gated analyte injections and electrophoretic separations in multilayer microfluidic architectures [J].
Cannon, DM ;
Kuo, TC ;
Bohn, PW ;
Sweedler, JV .
ANALYTICAL CHEMISTRY, 2003, 75 (10) :2224-2230
[4]   Radionuclide and metal ion detection on a capillary electrophoresis microchip using LED absorbance detection [J].
Collins, GE ;
Lu, Q .
SENSORS AND ACTUATORS B-CHEMICAL, 2001, 76 (1-3) :244-249
[5]   Microfabricated capillary electrophoresis sensor for uranium (VI) [J].
Collins, GE ;
Lu, Q .
ANALYTICA CHIMICA ACTA, 2001, 436 (02) :181-189
[6]   Nonaqueous based microchip separation of toxic metal ions using 2-(5-bromo-2-pyridylazo)-5-(N-propyl-N-sulfopropylamino)phenol [J].
Deng, G ;
Collins, GE .
JOURNAL OF CHROMATOGRAPHY A, 2003, 989 (02) :311-316
[7]   A selective, ratiometric fluorescent sensor for Pb2+ [J].
Deo, S ;
Godwin, HA .
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY, 2000, 122 (01) :174-175
[8]   Integrated chip-based capillary electrophoresis [J].
Effenhauser, CS ;
Bruin, GJM ;
Paulus, A .
ELECTROPHORESIS, 1997, 18 (12-13) :2203-2213
[9]  
EIJKEL JCT, 1999, ORGANIC MESOSCOPIC C, P185
[10]  
*EPA, 2000, EPA453R00005