Integrated microfluidic device for serum biomarker quantitation using either standard addition or a calibration curve.

Department of Chemistry and Biochemistry, Brigham Young University, Provo, Utah 84602, USA.
Analytical Chemistry (Impact Factor: 5.82). 10/2009; 81(19):8230-5. DOI: 10.1021/ac901566s
Source: PubMed

ABSTRACT Detection and accurate quantitation of biomarkers such as alpha-fetoprotein (AFP) can be a key aspect of early stage cancer diagnosis. Microfluidic devices provide attractive analysis capabilities, including low sample and reagent consumption, as well as short assay times. However, to date microfluidic analyzers have relied almost exclusively on calibration curves for sample quantitation, which can be problematic for complex mixtures such as human serum. We have fabricated integrated polymer microfluidic systems that can quantitatively determine fluorescently labeled AFP in human serum using either the method of standard addition or a calibration curve. Our microdevices couple an immunoaffinity purification step with rapid microchip electrophoresis separation in a laser-induced fluorescence detection system, all under automated voltage control in a miniaturized polymer microchip. In conjunction with laser-induced fluorescence detection, these systems can quantify AFP at approximately 1 ng/mL levels in approximately 10 microL of human serum in a few tens of minutes. Our polymer microdevices have been applied in determining AFP in spiked serum samples. These integrated microsystems offer excellent potential for rapid, simple, and accurate biomarker quantitation in a point-of-care setting.

  • [Show abstract] [Hide abstract]
    ABSTRACT: We reported the in situ synthesis and use of porous polymer monolith (PPM) columns in an integrated multilayer PDMS/glass microchip for microvalve-assisted on-line microextraction and microchip electrophoresis for the first time. Under the control of PDMS microvalves, the grafting of the microchannel surface and in situ photopolymerization of poly(methacrylic acid-co-ethylene glycol dimethacrylate) monolith in a defined zone were successfully achieved. Different factors including the surface grafting, polymerization time, PDMS elastic properties (ratio of oligomer/curing reagent) and UV intensity that affect the monolith synthesis in the PDMS microchannel were investigated and optimized. Dopamine, a model analyte, has been online microextracted, eluted, electrophoresized and electrochemically detected in the microchip, with a mean concentration enrichment factor of 80 (n=3). The results demonstrated that the PPM could be synthesized successfully in the PDMS microchip with a homogeneous structure and excellent mechanical properties. Furthermore, owing to the intrinsic character using PDMS in large-scale integrated microsystems, the implantation of PPM pretreatment units in PDMS microchips would make it possible to deal with complicated analytical processes in a high-throughput way.
    Electrophoresis 09/2010; 31(18):3028-34. · 3.26 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Recent advances in microfluidic systems, particularly in the Micro Total Analysis System (μTAS) or Lab On a Chip (LOC), drive the current analysis tools and equipment towards miniaturization, rapid at-line testing and mobility. The state-of-the-art microfluidic technology targets a wider range but smaller volumes of analytes, making the analytical procedure relatively easier and faster. This trend together with faster electronics and modern instrumentation systems will make real-time and in situ analysis a definite possibility. This review focuses on microchip capillary electrophoresis with amperometric detection (MCE-AD) for the detection of DNA and other electroactive analytes. The problems associated with the microchip design, in particular the choice of materials and the configuration of electrodes are discussed thoroughly and solutions are proposed. Significant developments in the related areas are also covered and reviewed critically.
    Talanta 07/2011; 85(1):28-34. · 3.50 Impact Factor
  • Chemical Reviews 02/2013; · 41.30 Impact Factor

Full-text (2 Sources)

Available from
Jun 1, 2014