2006 Progress Report: Integrated Microfluidic System for Bioluminescent Bioreporting, Separations, Vibrational Spectroscopy, and Microcantilever Transducer Evaluation of Endocrine Disrupting Chemicals

EPA Grant Number: R832740
Title: Integrated Microfluidic System for Bioluminescent Bioreporting, Separations, Vibrational Spectroscopy, and Microcantilever Transducer Evaluation of Endocrine Disrupting Chemicals
Investigators: Sepaniak, Michael J. , Sayler, Gary S.
Institution: University of Tennessee - Knoxville
EPA Project Officer: Hahn, Intaek
Project Period: November 1, 2005 through October 31, 2008 (Extended to October 31, 2009)
Project Period Covered by this Report: November 1, 2005 through October 31, 2006
Project Amount: $590,240
RFA: Exposure Measurement Tools for Endocrine Disrupting Chemicals in Mixtures (2005) RFA Text |  Recipients Lists
Research Category: Economics and Decision Sciences , Health , Safer Chemicals , Endocrine Disruptors

Objective:

The objective of this research is to develop analytical methodologies for the quantitative and qualitative measurement of mixtures of endocrine disrupting chemicals (EDCs) by utilizing the tools of analytical chemistry that include microcantilever arrays (MCAs) for nanomechanical sensing, surface enhanced Raman spectroscopy (SERS), and chemical separations with a complement by biosensing microorganisms. By improving the existing technology and attacking the problem of EDC exposure and activity monitoring in realistic mixtures with an arsenal of informative tools such as MCAs, SERS, and chemical separations, one can clarify and elucidate which chemicals, and in what combinations, can mimic or inhibit endocrine signaling molecules. Speed and portability of these analytical techniques, either on separate or partially integrated platforms, will greatly facilitate screening and characterization of samples in the field.

Progress Summary:

Accomplishments have been made in addressing specific tasks 1, 2, and 3, and are summarized below.

Task 1. Test an array of known EDCs in relevant matrices for SERS response characteristics to create a quantitative spectral library.

As described by the first of the three goals, our work in year 1 on EDCs has included successfully surveying a number of EDCs for SERS activity. Besides giving vibrational information to identify EDCs, SERS can be used to track chemical changes that occur in some EDCs as a result of exposure to light or oxidants, and investigation of that advantage for EDCs that change chemically is under way. Improvements in the regularity, sensitivity, and reproducibility of the SERS substrates are being made, and preconcentration and sample cleanup via solid phase extraction have been initiated and show promise at improving detectability.

Task 2. Develop EDC nanomechanical response signatures on ΜCAs treated with various molecular recognition phases (MRPs).

Progress has been most encouraging on this task: the development of nanomechanical responses to EDCs on ΜCAs treated with several different endocrine receptor proteins as MRPs. The interaction between EDCs and protein receptors or antibodies immobilized on a microcantilever (MC) surface induces an apparent surface stress. This surface stress leads to static bending of the MC, which is detected by an optical beam bending technique. The combination of protein receptors, which include estrogen receptor beta (ER-β), as well as monoclonal antibodies (Ab; anti-17-β-ES), with MC systems employing modified nanostructured surfaces provides for excellent response sensitivity and the inherent selectivity of biospecific receptor-EDC interactions for screening and fundamental studies.

Task 3. Integrate bioreporter yeast into living conditions suitable for predictable function on a microfluidic platform, and optimize those conditions with electrophoretic separation parameters for EDCs.

The majority of progress on this task has been in developing capillary electrochromatographic separations of EDCs. Model separations were developed for mixtures of subsets of EDCs such as phytoestrogens, synthetic and natural hormones, and industrial chemicals using micellar electrokinetic chromatography performed on a commercial capillary electrophoresis instrument with UV-visible detection. In the near future, these methods will be transferred to a chip platform.

Our distinct, parallel studies on separations, SERS, and ΜCA detection indicate that all three may function best on separated or semi-separate platforms. Our testing will continue with the aim of maximizing the power of each technique as an exposure measurement tool for EDCs in mixtures, even if this means a delay in the complete system coming onto a single platform.

Future Activities:

Year 2 activities will focus on the following:

  • Increase sensitivity of SERS detection for EDCs via the three-pronged approach described above—our goal is low nanomolar detectability.
  • Bioaffinity approach to nanomechanics—our goals are the creation and testing of differential MCAs having different bioaffinity MRPs on different MCs for broad analyte screening and fundamental studies.
  • Optimize microfluidic chip-based separations of EDCs for several EDC mixtures.
  • Prepare and submit at least three manuscripts for peer-review; present at least two talks at meetings such as the Eastern Analytical Symposium (EAS), Federation of Analytical Chemistry and Spectroscopy Studies (FACSS), Pittsburgh Conference & Expo (PittCon), and U.S. Environmental Protection Agency (EPA) annual reporting conference.
  • Prepare and submit year 2 report.


Journal Articles on this Report : 3 Displayed | Download in RIS Format

Other project views: All 53 publications 30 publications in selected types All 30 journal articles
Type Citation Project Document Sources
Journal Article Archibald R, Datskos P, Devault G, Lamberti V, Lavrik N, Noid D, Sepaniak M, Dutta P. Independent component analysis of nanomechanical responses of cantilever arrays. Analytica Chimica Acta 2007;584(1):101-105. R832740 (2006)
R832740 (2007)
R832740 (2008)
R832740 (Final)
  • Abstract from PubMed
  • Full-text: ScienceDirect-Full Text HTML
    Exit
  • Abstract: ScienceDirect-Abstract
    Exit
  • Other: ScienceDirect-Full Text PDF
    Exit
  • Journal Article Chapman PJ, Vogt F, Dutta P, Datskos PG, Devault GL, Sepaniak MJ. Facile hyphenation of gas chromatography and a microcantilever array sensor for enhanced selectivity. Analytical Chemistry 2007;79(1):364-370. R832740 (2006)
    R832740 (2007)
    R832740 (2008)
    R832740 (Final)
  • Abstract from PubMed
  • Full-text: ACS-Full Text HTML
    Exit
  • Abstract: ACS-Abstract
    Exit
  • Other: ACS-Full Text PDF
    Exit
  • Journal Article Wellman AD, Sepaniak MJ. Magnetically-assisted transport evanescent field fluoroimmunoassay. Analytical Chemistry 2006;78(13):4450-4456. R832740 (2006)
    R832740 (2007)
    R832740 (2008)
    R832740 (Final)
  • Abstract from PubMed
  • Full-text: ACS-Full Text HTML
    Exit
  • Abstract: ACS-Abstract
    Exit
  • Other: ACS-Full Text PDF
    Exit
  • Supplemental Keywords:

    CE-SERS, MEMS, nanomechanics, BLYES, estrogen detection, androgen detection,, RFA, Health, Scientific Discipline, Health Risk Assessment, Endocrine Disruptors - Environmental Exposure & Risk, endocrine disruptors, Microbiology, Biochemistry, Endocrine Disruptors - Human Health, endocrine disruptor screening program, microcantilever transducer evaluation, bioavailability, EDCs, endocrine disrupting chemicals, exposure studies, bioluminescent testing

    Progress and Final Reports:

    Original Abstract
  • 2007 Progress Report
  • 2008 Progress Report
  • Final Report