Capillary Immunophoresis for Environmental MonitoringEPA Grant Number: R823292
Title: Capillary Immunophoresis for Environmental Monitoring
Investigators: Lee, Cheng S.
Institution: University of Maryland
Current Institution: University of Maryland , Iowa State University
EPA Project Officer: Hahn, Intaek
Project Period: October 1, 1995 through September 1, 1998
Project Amount: $269,984
RFA: Exploratory Research - Environmental Biology (1995) RFA Text | Recipients Lists
Research Category: Biology/Life Sciences , Health , Ecosystems
The proposed capillary immunophoresis as a novel environmental monitoring tool combines the strengths of both capillary electrophoresis in the ease and speed of analyses and the antigen-antibody reaction in biospecificity and sensitivity. In analogy to a two-dimensional separation system, micellar electrokinetic capillary chromatography (MECC) as the first dimension separates the structurally related pollutants such as triazine herbicides based on their differential partitioning with the micellar phase. Environmental pollutants separated by MECC can be discriminated against other sample components by immunocomplex formation in a post-capillary immunoreactor. Immunoreaction as the second dimension utilizes the antibody's cross-reactivity for the recognition of triazines with a common structural element (epitope). The direct sensing of the antigen (triazines)-antibody reaction is achieved by monitoring the fluorescence polarization of atrazine hapten-fluorochrome conjugate in a competitive immunoassay format.
The proposed research is a fundamental effort in the development of capillary immunophoresis as a novel hybrid analytical technique, exhibiting the analytical power of separation and immunoselectivity for the identification of unknown contaminants in complex sample matrix. More specifically, the objectives are to study: 1) the effect of electroosmotic control on the separation resolution of contaminants in MECC; 2) the quantitative dependence of solution ionic strengths and capillary dimensions on the effectiveness of mass transfer and mixing of pollutants with antibodies in the post-column immunoreactor; and 3) the direct sensing of the antigen-antibody reaction by measuring the fluorescence polarization of hapten-fluorochrome conjugate in an on-column laser-induced fluorescence detector. The integration of MECC with on-line immunodetection for multiresidue analysis of environmental pollutants will be demonstrated by using triazine herbicides and 4-nitrophenol derivatives as two model systems.