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Updated: Jan 28, 2026
11:04
Biomolecular Detection employing the Interferometric Reflectance Imaging Sensor IRIS
Published on: May 3, 2011
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Intensity-modulated nanoplasmonic interferometric sensor for MMP-9 detection
Yifeng Qian1, Xie Zeng, Yongkang Gao
1Electrical and Computer Engineering Department, Lehigh University, Bethlehem, PA 18015, USA. fjb205@lehigh.edu.
Lab on a Chip
|March 2, 2019
Summary
We developed a novel nanoplasmonic biosensor for label-free detection of molecular secretion from immune cells. This sensitive platform offers high temporal resolution and spatial accuracy for studying cell signaling dynamics.
Area of Science:
- Nanoplasmonics
- Biosensing Technology
- Cellular Immunology
Background:
- Understanding immune cell secretion is crucial for elucidating cellular functions.
- Existing methods for detecting molecular secretion often require labeling and lack dynamic, high-resolution capabilities.
Purpose of the Study:
- To develop a label-free, dynamic biosensing platform for monitoring molecular secretion from immune cells.
- To achieve high sensitivity, temporal resolution, and spatial accuracy in detecting secreted biomolecules.
Main Methods:
- Development of a nanoplasmonic circular interferometric biosensor utilizing intensity interrogation.
- Coupling of free light and surface plasmon polariton (SPP) waves for enhanced sensitivity.
- Simultaneous monitoring of multiple sensing units using a simple collinear optical setup with an LED source and CCD camera.
Main Results:
- Achieved a refractive index unit (RIU) resolution of 4.1 × 10-5 for a single sensor unit with 1-second temporal resolution.
- A 12 × 12 sensor array demonstrated a resolution of 7.3 × 10-6 RIU.
- Successfully detected matrix metalloproteinase 9 (MMP-9) secretion from THP-1 cells, correlating with ELISA results but without labeling.
Conclusions:
- The developed nanoplasmonic biosensor array offers superior spatial, temporal, and mass resolution compared to existing label-free technologies.
- This platform holds significant potential for studying the dynamics of cell secretion and understanding single-cell functions within microfluidic systems.
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