A nanoparticle amplification based quartz crystal microbalance DNA sensor for detection of Escherichia coli O157:H7

• Published in: Biosensors & bioelectronics Vol. 21; no. 7; pp. 1178 - 1185
• Main Authors: Mao, Xiaole, Yang, Liju, Su, Xiao-Li, Li, Yanbin
• Format: Journal Article
• Language: English
• Published: Lausanne Elsevier B.V 15.01.2006; Elsevier Science
• Subjects: Biological and medical sciences; Biosensing Techniques - instrumentation; Biosensing Techniques - methods; Biosensors; Biotechnology; Colony Count, Microbial - instrumentation; Colony Count, Microbial - methods; DNA sensor; DNA, Bacterial - analysis; DNA, Bacterial - genetics; E. coli O157:H7; Electrochemistry - instrumentation; Electrochemistry - methods; Equipment Design; Equipment Failure Analysis; Escherichia coli; Escherichia coli O157 - genetics; Escherichia coli O157 - isolation & purification; Fundamental and applied biological sciences. Psychology; Methods. Procedures. Technologies; Nanoparticle amplification; Nanotubes - chemistry; Oligonucleotide Array Sequence Analysis - instrumentation; Oligonucleotide Array Sequence Analysis - methods; Particle Size; Polymerase Chain Reaction - instrumentation; Polymerase Chain Reaction - methods; QCM; Quartz; Various methods and equipments; E. coli O157:H7; QCM; DNA sensor; Nanoparticle amplification; Molecular hybridization; Nanoparticle; Escherichia coli; Amplification; Biosensor; DNA; Bacteria; Detection; E. coli 0157:H7; Enterobacteriaceae; Quartz microbalance
• ISSN: 0956-5663; 1873-4235
• DOI: 10.1016/j.bios.2005.04.021

A quartz crystal microbalance (QCM) DNA sensor, based on the nanoparticle amplification method, was developed for detection of Escherichia coli O157:H7. A thiolated single-stranded DNA (ssDNA) probe specific to E. coli O157:H7 eaeA gene was immobilized onto the QCM sensor surface through self-assembly. The hybridization was induced by exposing the ssDNA probe to the complementary target DNA, and resulted in the mass change and therefore frequency change of the QCM. Streptavidin conjugated Fe 3O 4 nanoparticles (average diameter = 145 nm) were used as “mass enhancers” to amplify the frequency change. Synthesized biotinylated oligonucleotides as well as E. coli O157:H7 eaeA gene fragments (151 bases) amplified using asymmetric PCR with biotin labeled primers were tested. As low as 10 −12 M synthesized oligonucleotides and 2.67 × 10 2 colony forming unit (CFU)/ml E. coli O157:H7 cells can be detected by the sensor. Linear correlation between frequency change and logarithmic number of bacterial cell concentration was found for E. coli O157:H7 from 2.67 × 10 2 to 2.67 × 10 6 CFU/ml.