Electrochemiluminescence DNA sensor array for multiplex detection of biowarfare agents

• Published in: Analytical and bioanalytical chemistry 2015-09, Vol.407 (22), p.6657-6667
• Main Authors: Spehar-Délèze, Anna-Maria, Gransee, Rainer, Martinez-Montequin, Sergio, Bejarano-Nosas, Diego, Dulay, Samuel, Julich, Sandra, Tomaso, Herbert, O’Sullivan, Ciara K
• Format: Article
• Language: English
• Subjects: activated carbon; adsorption; Analytical Chemistry; Assaying; Automation; Bacteria - isolation & purification; Bacterial infections; Biochemistry; Biological & chemical terrorism; Biological Warfare Agents - classification; Biosensing Techniques - instrumentation; Carbon; Characterization and Evaluation of Materials; Chemistry; Chemistry and Materials Science; Conductometry - instrumentation; cross reaction; Deoxyribonucleic acid; detection limit; Detection limits; DNA; DNA - analysis; DNA - chemistry; Electrochemiluminescence; Electrodes; Electroluminescence; Electronics; Electrons; Equipment Design; Equipment Failure Analysis; Food Science; hybridization; Laboratory Medicine; Luminescent Measurements - instrumentation; Microarray Analysis - instrumentation; Monitoring/Environmental Analysis; Multiplexing; Paper in Forefront; Pathogens; Probes; Proteins; Quantum dots; Reproducibility of Results; Sensitivity and Specificity; Sensor arrays; Sensors; silver chloride
• ISSN: 1618-2642; 1618-2650
• DOI: 10.1007/s00216-015-8831-y

Development of a fully automated electrochemiluminescence (ECL) DNA assay for multiplex detection of six biowarfare agents is described. Aminated-DNA capture probes were covalently immobilised on activated-carbon electrodes and subsequently hybridised to target strands. Detection was achieved via a sandwich-type assay after Ru(bpy)₃ ²⁺-labelled reporter probes were hybridised to the formed probe–target complexes. The assay was performed in an automated microsystem in a custom-designed ECL detection box with integrated fluidics, electronics, and movable photomultiplier detector. The obtained limits of detection were 0.6–1.2 nmol L⁻¹ for six targets ranging from 50 to 122 base pairs in size, with linear range 1–15 nmol L⁻¹. Non-specific adsorption and cross-reactivity were very low. Detection of six targets on a single chip was achieved with subnanomolar detection limits. Graphical Abstract A photo of the electrode array containing 3 × 14 carbon working electrodes (WE), a common carbon counter electrode (CE), and Ag/AgCl reference electrode (RE) (top). The detection scheme is indicated for one WE. First, probe sequences were covalently immobilised on the activated-carbon surface, then target strands were introduced, and finally Ru(bpy)₃ ²⁺-labelled reporter strands were introduced to complete the sandwich-type hybridisation assay.