Bacteria detection using disposable optical leaky waveguide sensors

• Published in: Biosensors & bioelectronics Vol. 21; no. 2; pp. 293 - 302
• Main Authors: Zourob, Mohammed, Mohr, Stephan, Brown, Bernard J. Treves, Fielden, Peter R., McDonnell, Martin B., Goddard, Nicholas J.
• Format: Journal Article
• Language: English
• Published: Lausanne Elsevier B.V 15-08-2005; Elsevier Science
• Subjects: Bacillus - isolation & purification; Bacillus subtilis; Bacteria detection; Biological and medical sciences; Biosensing Techniques - instrumentation; Biosensing Techniques - methods; Biosensor; Biosensors; Biotechnology; Colony Count, Microbial - instrumentation; Colony Count, Microbial - methods; Disposable sensor; Equipment Design; Equipment Failure Analysis; Evanescent wave sensor; Fundamental and applied biological sciences. Psychology; Leaky waveguide; Methods. Procedures. Technologies; Microfluidic Analytical Techniques - instrumentation; Microfluidic Analytical Techniques - methods; Optical waveguide; Optics and Photonics - instrumentation; Refractometry - instrumentation; Refractometry - methods; Spectrometry, Fluorescence - instrumentation; Spectrometry, Fluorescence - methods; Spores, Bacterial - isolation & purification; Transducers; Various methods and equipments; Bacteria detection; Disposable sensor; Optical waveguide; Leaky waveguide; Evanescent wave sensor; Biosensor; Disposable; Leaky waveguide: Bacteria detection: Biosensor: Disposable sensor; Detector; Optical method; Bacteria; Detection; Evanescent wave; Waveguide
• ISSN: 0956-5663; 1873-4235
• DOI: 10.1016/j.bios.2004.10.013

Novel disposable absorbing material clad leaky waveguide sensor devices (LWD) have been developed for the detection of pathogenic particles such as bacteria. These chips are tailored to give the maximum extension of the evanescent field at the sensor surface in order to place the entire volume of the bacteria captured by immobilized antibodies on the chip surface within this field. This in turn increases the interaction of the light with the bacteria's bulk volume. Disposable LWD chips were fabricated at room temperature and without the use of expensive fabrication equipment. These LWDs have been characterised by detecting refractive index (RI) changes, scattering and fluorescence from bacterial spores at the sensor surface when illuminated at the coupling angle. The detection limit of
Bacillus subtilis var.
niger (BG) bacterial spores was 10
4
spores/ml and the illumination intensity of the spores was found to be three times greater than the illumination intensity generated using the surface plasmon resonance (SPR).