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An AC electrokinetics facilitated biosensor cassette for rapid pathogen identification.

ABSTRACT: To develop a portable point-of-care system based on biosensors for common infectious diseases such as urinary tract infection, the sensing process needs to be implemented within an enclosed fluidic system. On chip sample preparation of clinical samples remains a significant obstacle to achieving robust sensor performance. Herein AC electrokinetics is applied in an electrochemical biosensor cassette to enhance molecular convection and hybridization efficiency through electrokinetics induced fluid motion and Joule heating induced temperature elevation. Using E. coli as an exemplary pathogen, we determined the optimal electrokinetic parameters for detecting bacterial 16S rRNA in the biosensor cassette based on the current output, signal-to-noise ratio, and limit of detection. In addition, a panel of six probe sets targeting common uropathogenic bacteria was demonstrated. The optimized parameters were also validated using patient-derived clinical urine samples. The effectiveness of electrokinetics for on chip sample preparation will facilitate the implementation of point-of-care diagnosis of urinary tract infection in the future.

SUBMITTER: Ouyang M

PROVIDER: S-EPMC3709570 | biostudies-literature | 2013 Jul

REPOSITORIES: biostudies-literature

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An AC electrokinetics facilitated biosensor cassette for rapid pathogen identification.

Ouyang Mengxing M Mohan Ruchika R Lu Yi Y Liu Tingting T Mach Kathleen E KE Sin Mandy L Y ML McComb Mason M Joshi Janhvi J Gau Vincent V Wong Pak Kin PK Liao Joseph C JC

The Analyst 20130701 13

To develop a portable point-of-care system based on biosensors for common infectious diseases such as urinary tract infection, the sensing process needs to be implemented within an enclosed fluidic system. On chip sample preparation of clinical samples remains a significant obstacle to achieving robust sensor performance. Herein AC electrokinetics is applied in an electrochemical biosensor cassette to enhance molecular convection and hybridization efficiency through electrokinetics induced fluid ...[more]

PMID: 23626988

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Project description:BACKGROUND: Hand, foot and mouth disease (HFMD) is caused by members of the family Picornaviridae in the genus Enterovirus. It has been reported that coxsackievirus A6 (CVA6) infections are emerging as a new and major cause of epidemic HFMD. Sporadic HFMD cases positive for CVA6 were detected in the mainland of China in recent years. To strengthen the surveillance of CVA6 infections and outbreak control, the clinical diagnosis is urgently needed to distinguish the CVA6 infection disease from other infections. METHODS: In order to develop a sensitive quantitative real-time RT-PCR assay for rapid detection of CVA6 RNA, primers and probe were designed to target the VP1 gene segment of CVA6. The conservation of the target segment was firstly analyzed by bioinformatic technology. The specificity of the real-time RT-PCR was further confirmed by detecting other related viruses and standard curves were established for the sensitivity evaluation. The pharyngeal swab samples from the EV71 and CVA16 unrelated HFMD patients were applied for CVA6 detection through the established method. RESULTS: Based on the primer-probe set to detect the target VP1 gene segment of CVA6, the quantitative real-time RT-PCR assay could discriminate CVA6 infection from other resemble viral diseases with a potential detection limit of 10 viral copies/ml. The specificity of the assay was determined by sequence alignment and experimentally tested on various related viruses. The standard curve showed that the amplification efficiency of templates with different concentrations of templates was almost the same (R2 >0.99). Evaluation of the established method with pharyngeal swabs samples showed good accordance with the results from serology diagnosis. CONCLUSION: This study is the first report developing a VP1 gene-based quantitative real-time RT-PCR for rapid, stable and specific detection of CVA6 virus. The real-time RT-PCR established in this study can be used as a reliable method for early diagnosis of CVA6 infection.

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An AC electrokinetics facilitated biosensor cassette for rapid pathogen identification.

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An AC electrokinetics facilitated biosensor cassette for rapid pathogen identification.

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