EurekaMag.com logo
+ Site Statistics
References:
53,869,633
Abstracts:
29,686,251
+ Search Articles
+ Subscribe to Site Feeds
EurekaMag Most Shared ContentMost Shared
EurekaMag PDF Full Text ContentPDF Full Text
+ PDF Full Text
Request PDF Full TextRequest PDF Full Text
+ Follow Us
Follow on FacebookFollow on Facebook
Follow on TwitterFollow on Twitter
Follow on LinkedInFollow on LinkedIn

+ Translate

Competitive multi-immunosensing of pesticides based on the particle manipulation with negative dielectrophoresis



Competitive multi-immunosensing of pesticides based on the particle manipulation with negative dielectrophoresis



Biosensors & Bioelectronics 25(8): 1928-1933



In this work, we have applied particle manipulation based on negative dielectrophoresis (n-DEP) to develop rapid and separation-free immunosensing systems. Two widely used pesticides, atrazine and bromopropylate, were used as target molecules to demonstrate competitive immunosensing based on the rapid manipulation of microparticles. A suspension of the fluorescence microparticles modified with a specific antibody was injected into the n-DEP device consisting of the interdigitated microarray (IDA) electrode and indium-tin-oxide (ITO) substrate immobilized by protein conjugation with antigen. The application of 2 MHz AC voltage (16 V peak-to-peak) to the IDA forced most of the particles to form a line pattern on the upper ITO over the gaps of IDA within 60s. In the absence of analytes, patterned microparticles were irreversibly captured on the ITO by the construction of immuno-complexes. When the microparticles bearing anti-atrazine IgG antibody were suspended in an analyte (atrazine) solution, irreversible capturing of microparticles on the ITO was inhibited because of the occupation of the binding sites of the antibodies with free-atrazine. As a result, the analyte molecules were re-dispersed from the ITO to disintegrate the line formation after turning off the voltage. We could discriminatively detect the fluorescence intensity of the captured microparticles at the designated areas from that of the uncaptured microparticles suspended in the solution. Thus, the separation steps usually required for conventional immunoassay are eliminated in the present procedure. A pre-incubation of microparticles for 3 min in an orange juice solution containing analyte allowed for the determination of the atrazine and bromopropylate concentrations with a limit of detection of 4 and 1.5 microg L(-1), respectively, providing sufficient detectability to achieve international regulations regarding pesticide residues in food samples. The assay was significantly accelerated by the rapid particle manipulation with n-DEP and totally accomplished within 5 min. We also demonstrated the possibility of the simultaneous determination of two pesticide residues by using the DEP devices with two channels modified with specific competitors for atrazine and bromopropylate.

(PDF emailed within 0-6 h: $19.90)

Accession: 052254700

Download citation: RISBibTeXText

PMID: 20129771

DOI: 10.1016/j.bios.2010.01.006



Related references

Rapid and separation-free sandwich immunosensing based on accumulation of microbeads by negative-dielectrophoresis. Biosensors & Bioelectronics 24(4): 1006-1011, 2008

Dielectrophoresis-based particle exchanger for the manipulation and surface functionalization of particles. Lab on A Chip 8(2): 267-273, 2008

A tapered aluminium microelectrode array for improvement of dielectrophoresis-based particle manipulation. Sensors 15(5): 10973-10990, 2015

Rapid and simple immunosensing system for simultaneous detection of tumor markers based on negative-dielectrophoretic manipulation of microparticles. Talanta 81(1-2): 657-663, 2010

Negative dielectrophoresis-based particle separation by size in a serpentine microchannel. Electrophoresis 32(5): 527-531, 2011

Development of a new contactless dielectrophoresis system for active particle manipulation using movable liquid electrodes. Electrophoresis 35(14): 2014-2021, 2015

Three-dimensional cell manipulation and patterning using dielectrophoresis via a multi-layer scaffold structure. Lab on A Chip 15(3): 920-930, 2016

A combined dielectrophoresis, traveling wave dielectrophoresis and electrorotation microchip for the manipulation and characterization of human malignant cells. Journal of Microbiological Methods 58(3): 387-401, 2004

Particle trapping in high-conductivity media with electrothermally enhanced negative dielectrophoresis. Analytical Chemistry 81(6): 2303-2310, 2010

Experimental study of dielectrophoresis and liquid dielectrophoresis mechanisms for particle capture in a droplet. Electrophoresis 32(11): 1337-1347, 2011

Characterization of the geometry of negative dielectrophoresis traps for particle immobilization in digital microfluidic platforms. Lab on A Chip 13(9): 1823-1830, 2013

Assessment of cell viability after manipulation with insulator-based dielectrophoresis. Electrophoresis 36(13): 1479-1484, 2016

Round-tip dielectrophoresis-based tweezers for single micro-object manipulation. Biosensors & Bioelectronics 47: 206-212, 2014

Protein manipulation with insulator-based dielectrophoresis and direct current electric fields. Journal of Chromatography. A 1206(1): 45-51, 2008

Dielectrophoresis-based cell manipulation using electrodes on a reusable printed circuit board. Lab on A Chip 9(15): 2224-2229, 2009