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Updated: May 28, 2026
10:44
Snap Chip for Cross-reactivity-free and Spotter-free Multiplexed Sandwich Immunoassays
Published on: November 13, 2017
Competitive, non-competitive, and mixed format cleavable tag immunoassays
Yupaporn Sameenoi1, Meghan M Mensack, Brian M Murphy
1Department of Chemistry, Colorado State University, Fort Collins, CO 80523, USA.
Methods (San Diego, Calif.)
|October 6, 2011
Summary
This study introduces a novel multiplexed immunoassay, cleavable tag immunoassay (CTI), capable of simultaneously detecting proteins and small molecules. CTI demonstrates high sensitivity for biomarkers like 3-nitrotyrosine, thyroxine, and C-reactive protein, advancing diagnostic capabilities.
Area of Science:
- Biochemistry
- Analytical Chemistry
- Immunology
Background:
- Immunoassays are crucial for diagnostics, drug analysis, and environmental monitoring due to antibody-antigen specificity.
- Multiplexed immunoassays offer enhanced efficiency for analyzing multiple biomarkers simultaneously.
Purpose of the Study:
- To develop and validate a multiplexed immunoassay, cleavable tag immunoassay (CTI), for simultaneous detection of protein and small molecule biomarkers.
- To demonstrate the CTI's capability in competitive, non-competitive, and mixed assay formats.
Main Methods:
- Cleavable tag immunoassay (CTI) performed in competitive, non-competitive, and mixed formats.
- Microchip capillary electrophoresis (MCE) with fluorescence detection for analyzing cleaved fluorescent tags.
- Model analytes: 3-nitrotyrosine (3-NT), thyroxine (T4), and C-reactive protein (CRP).
Main Results:
- Simultaneous detection of 3-NT and T4 using competitive CTI.
- Detection of CRP using non-competitive CTI.
- Established limits of detection (LOD): 0.5 μg/mL for 3-NT, 23 nM for T4, and 5 μg/mL for CRP.
- First report of mixed-format CTI for simultaneous protein (CRP) and small molecule (3-NT) detection.
Conclusions:
- CTI effectively detects proteins and small molecules within clinical reference ranges.
- The developed CTI platform enables simultaneous analysis of diverse biomarkers, offering a versatile diagnostic tool.
- This work highlights the potential of CTI for simultaneous biomarker analysis in various applications.
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