Title :
Characterization and optimization of an optical DNA hybridization sensor for the detection of multi-drug resistant tuberculosis
Author :
Sweeney, M.M.M. ; Bertolino, C. ; Berney, H. ; Sheehan, M.M.
Author_Institution :
Nat. Microelectron. Res. Centre, Cork, Ireland
Abstract :
The development of an optical DNA hybridization biosensor based on ruthenium electrochemiluminescence (ECL) was designed to detect DNA hybridization, using the detection of specific DNA sequences, which are indicative for antibiotic resistant strains of Mycobacterium tuberculosis as a model. The development of the sensor involved the characterization and optimization of the individual elements of the biosensor. Using this approach it was possible to ensure that the complete biosensor system was optimized to its maximum sensitivity for the electrochemiluminescent optical signal, which is produced during the DNA hybridization event. The transduction element used in this work is a solid-state silicon PIN photodiode. The miniaturization of the optical element to 5 mm2 and smaller has made it possible to integrate the optical element internally as part of the biosensor scheme. Ruthenium ECL is a chemiluminescent reaction that is initiated by electrical stimulation. Photolithographic techniques were used to deposit and pattern gold electrodes directly onto the surface of the PIN photodiodes for the initiation of the ECL reaction. The gold electrodes also act as a biological support layer for DNA immobilization via thiol -gold linkage chemistry. The characterization and optimization of the individual components of this biosensor have allowed us to fabricate a miniaturized and integrated system that is compatible with a flow-through system.
Keywords :
DNA; bio-optics; biomedical transducers; chemiluminescence; diseases; drugs; gold; micromechanical devices; molecular biophysics; p-i-n photodiodes; photolithography; ruthenium; Au; DNA immobilization; DNA sequences; Mycobacterium tuberculosis; Ru; electrical stimulation; electrochemiluminescent optical signal; gold electrodes; multi-drug resistant tuberculosis detection; optical DNA hybridization sensor; photolithography; solid-state silicon PIN photodiode; thiol-gold linkage chemistry; Biomedical optical imaging; Biosensors; Chemical elements; DNA; Immune system; Integrated optics; Optical sensors; PIN photodiodes; Sensor phenomena and characterization; Stimulated emission; Biosensors; DNA hybridization; Mycobacterium tuberculosis; electrochemiluminescence; ruthenium;
Conference_Titel :
Engineering in Medicine and Biology Society, 2004. IEMBS '04. 26th Annual International Conference of the IEEE
Conference_Location :
San Francisco, CA
Print_ISBN :
0-7803-8439-3
DOI :
10.1109/IEMBS.2004.1403579