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Updated: Feb 25, 2026
Multimodal Analytical Platform on a Multiplexed Surface Plasmon Resonance Imaging Chip for the Analysis of Extracellular Vesicle Subsets
Published on: March 17, 2023
Lipopolysaccharides detection on a grating-coupled surface plasmon resonance smartphone biosensor
Jinling Zhang1, Imran Khan2, Qingwen Zhang3
1School of Materials Science and Engineering, Centre for Biomimetic Sensor Science, Nanyang Technological University, 50 Nanyang Avenue, 637553, Singapore; School of Ophthalmology&Optometry, Eye Hospital, School of Biomedical Engineering, Wenzhou Medical University, Wenzhou 325001, PR China.
This study presents a smartphone biosensor for detecting endotoxins (LPS) using grating-coupled surface plasmon resonance. The portable device achieved a 32.5ng/mL detection limit, showing promise for point-of-care diagnostics.
Area of Science:
- Biomedical Engineering
- Analytical Chemistry
- Nanotechnology
Background:
- Surface Plasmon Resonance (SPR) is a powerful label-free sensing technique.
- Existing SPR systems often require bulky and expensive equipment, limiting their use in point-of-care settings.
- Lipopolysaccharides (endotoxins) are critical contaminants in medical applications requiring sensitive detection methods.
Purpose of the Study:
- To develop a portable, label-free biosensor platform utilizing smartphone technology for endotoxin detection.
- To integrate Grating-Coupled Surface Plasmon Resonance (GC-SPR) with a smartphone for simplified spectral analysis.
- To demonstrate the sensor's capability for detecting lipopolysaccharides (LPS) in various matrices, including clinical fluids.
Main Methods:
- A smartphone-based GC-SPR system was constructed using the phone's camera and flash, a compact disk (CD) as a dispersive element, and a disposable gold (Au) diffraction grating sensor chip.
- The Au grating sensor chip was functionalized with a synthetic peptide receptor specific for LPS.
- The platform's performance was evaluated for LPS detection in water and clinically relevant injectable fluids.
Main Results:
- The developed GC-SPR biosensor achieved a limit of detection of 32.5 ng/mL for LPS in water.
- The sensor demonstrated good selectivity for LPS in the presence of various interfering molecules.
- Feasibility was shown for detecting LPS in common intravenous fluids like 0.9% sodium chloride, compound sodium lactate, and insulin aspart.
Conclusions:
- A portable and simple smartphone-based GC-SPR biosensor platform for label-free LPS detection has been successfully developed.
- The system's ability to detect LPS in clinical injectable fluids highlights its potential for point-of-care applications.
- This technology offers a promising approach for rapid, cost-effective, and remote monitoring of endotoxins in biomedical and environmental contexts.
