title: Electrokinetic stringency control in self-assembled monolayer-based biosensors for multiplex urinary tract infection diagnosis.
abstract: Rapid detection of bacterial pathogens is critical toward judicious management of infectious diseases. Herein, we demonstrate an in situ electrokinetic stringency control approach for a self-assembled monolayer-based electrochemical biosensor toward urinary tract infection diagnosis. The in situ electrokinetic stringency control technique generates Joule heating induced temperature rise and electrothermal fluid motion directly on the sensor to improve its performance for detecting bacterial 16S rRNA, a phylogenetic biomarker. The dependence of the hybridization efficiency reveals that in situ electrokinetic stringency control is capable of discriminating single-base mismatches. With electrokinetic stringency control, the background noise due to the matrix effects of clinical urine samples can be reduced by 60%. The applicability of the system is demonstrated by multiplex detection of three uropathogenic clinical isolates with similar 16S rRNA sequences. The results demonstrate that electrokinetic stringency control can significantly improve the signal-to-noise ratio of the biosensor for multiplex urinary tract infection diagnosis.
  
  
  BACKGROUND
  Urinary tract infections remain a significant cause of mortality and morbidity as secondary conditions often related to chronic diseases or to immunosuppression. Rapid and sensitive identification of the causative organisms is critical in the appropriate management of this condition. These investigators demonstrate an in situ electrokinetic stringency control approach for a self-assembled monolayer-based electrochemical biosensor toward urinary tract infection diagnosis, establishing that such an approach significantly improves the biosensor's signal-to-noise ratio.
authors.affiliation: Department of Aerospace and Mechanical Engineering, University of Arizona, Tucson, AZ, USA.
authors.forename: Tingting
authors.initials: T
authors.lastname: Liu
authors.affiliation: Department of Aerospace and Mechanical Engineering, University of Arizona, Tucson, AZ, USA; Department of Urology, Stanford University, Stanford, CA, USA.
authors.forename: Mandy L Y
authors.initials: ML
authors.lastname: Sin
authors.affiliation: Department of Aerospace and Mechanical Engineering, University of Arizona, Tucson, AZ, USA.
authors.forename: Jeff D
authors.initials: JD
authors.lastname: Pyne
authors.affiliation: GeneFluidics Inc., Irwindale, CA, USA.
authors.forename: Vincent
authors.initials: V
authors.lastname: Gau
authors.affiliation: Department of Urology, Stanford University, Stanford, CA, USA; Veterans Affairs Palo Alto Health Care System, Palo Alto, CA, USA.
authors.forename: Joseph C
authors.initials: JC
authors.lastname: Liao
authors.affiliation: Department of Aerospace and Mechanical Engineering, University of Arizona, Tucson, AZ, USA. Electronic address: pak@email.arizona.edu.
authors.forename: Pak Kin
authors.initials: PK
authors.lastname: Wong
mesh_terms: D015415:Biomarkers / Q000652:urine*; D015374:Biosensing Techniques; D013293:Enterococcus faecalis / Q000235:genetics / Q000302:isolation & purification; D004926:Escherichia coli / Q000235:genetics / Q000302:isolation & purification; D006801:Humans; D010802:Phylogeny; D011513:Proteus mirabilis / Q000235:genetics / Q000302:isolation & purification; D011550:Pseudomonas aeruginosa / Q000235:genetics / Q000302:isolation & purification; D012336:RNA, Ribosomal, 16S / Q000235:genetics*; D057790:Staphylococcus saprophyticus / Q000235:genetics / Q000302:isolation & purification; D014552:Urinary Tract Infections / Q000175:diagnosis* / Q000235:genetics / Q000382:microbiology; D059349:Urine Specimen Collection
chemical_list: D015415:Biomarkers; D012336:RNA, Ribosomal, 16S
keywords: Matrix effects; Multiplex detection; Self-assembled monolayers; Stringency control; Urinary tract infection
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