Portable evanescent wave fiber biosensor for highly sensitive detection of Shigella.
A portable evanescent wave fiber biosensor was developed to achieve the rapid and highly sensitive detection of Shigella. In this study, a DNA probe was covalently immobilized onto fiber-optic biosensors that can hybridize with a fluorescently labeled complementary DNA. The sensitivity of detection for synthesized oligonucleotides can reach 10(-10) M. The surface of the sensor can be regenerated with 0.5% sodium dodecyl sulfate solution (pH 1.9) for over 30 times without significant deterioration of performance. The total analysis time for a single sample, including the time for measurement and surface regeneration, was less than 6 min. We employed real-time polymerase chain reaction (PCR) and compared the results of both methods to investigate the actual Shigella DNA detection capability of the fiber-optic biosensor. The fiber-optic biosensor could detect as low as 10(2) colony-forming unit/mL Shigella. This finding was comparable with that by real-time PCR, which suggests that this method is a potential alternative to existing detection methods.
Beijing Institute of Radiation Medicine, Beijing 100850, PR China. Electronic address: ruixiao203@sina.com.
Rui
R
Xiao
Beijing Institute of Radiation Medicine, Beijing 100850, PR China.
Zhen
Z
Rong
School of Environment and Natural Resources, Renmin University of China, Beijing 100872, PR China.
Feng
F
Long
Beijing Institute of Radiation Medicine, Beijing 100850, PR China.
Qiqi
Q
Liu
D015374:Biosensing Techniques / Q000295:instrumentation* / Q000379:methods*; D004269:DNA, Bacterial / Q000032:analysis / Q000235:genetics; D055100:Optical Fibers; D060888:Real-Time Polymerase Chain Reaction; D012760:Shigella / Q000235:genetics / Q000302:isolation & purification*; D012815:Signal Processing, Computer-Assisted; D013698:Templates, Genetic
D004269:DNA, Bacterial
Biosensor; Evanescent wave; Fiber-optic biosensor; Fluorescence signal