Noncompetitive Fluorescence Polarization Immunoassay for Protein Determination
Mao Fukuyama1, Ayano Nakamura2, Keine Nishiyama2
1Institute of Multidisciplinary Research for Advanced Materials, Tohoku University, Katahira 2-1-1, Aoba-ku, Sendai 980-8577, Japan.
Analytical Chemistry
|October 23, 2020
Summary
A novel noncompetitive fluorescent polarization immunoassay (FPIA) utilizes variable domain of heavy chain camelid antibodies (VHH antibodies) for enhanced biomolecule detection. This method expands the quantitation range for large molecules like immunoglobulin G (IgG), improving point-of-care diagnostics.
Area of Science:
- Biochemistry
- Immunotechnology
- Analytical Chemistry
Background:
- Fluorescent polarization immunoassay (FPIA) is a valuable point-of-care diagnostic tool.
- Traditional FPIA methods are competitive assays, limiting their application for large biomolecules.
- The restricted applicability of FPIA hinders the detection of complex biological targets.
Purpose of the Study:
- To develop a noncompetitive FPIA method for improved detection of large biomolecules.
- To utilize the variable domain of the heavy chain of camelid antibodies (VHH antibodies) in FPIA.
- To demonstrate the efficacy of VHH-based FPIA for quantifying immunoglobulin G (IgG).
Main Methods:
- Development of a noncompetitive FPIA assay utilizing VHH antibodies.
- Quantitation of rabbit immunoglobulin G (IgG) using the developed FPIA method.
- Validation of the VHH-based FPIA with a portable instrument for human IgG detection in serum.
Main Results:
- The VHH-based FPIA successfully quantified rabbit IgG.
- The assay demonstrated a wider response range compared to assays using antibody-binding (Fab) fragments.
- A VHH-based immunoassay for human IgG in human serum was successfully demonstrated using a portable instrument.
Conclusions:
- Noncompetitive FPIA using VHH antibodies offers an improved method for detecting large biomolecules.
- This approach expands the utility of FPIA for sensitive and quantitative diagnostics.
- VHH antibody-based FPIA holds promise for advanced point-of-care testing applications.
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