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Published on: November 13, 2017
Development of a carboxymethyl chitosan functionalized slide for small molecule detection using oblique-incidence
Mengjing Xu1,2, Boyang Shi3, Haofeng Li1
1Department of Optical Science and Engineering, Shanghai Engineering Research Center of Ultra-Precision Optical Manufacturing, Key Laboratory of Micro and Nano Photonic Structures (Ministry of Education), School of Information Science and Technology, Fudan University, Shanghai 200433, China.
This study enhances label-free optical biosensors for detecting small molecules using a novel 3D biochip. The improved oblique-incidence reflectivity difference (OI-RD) technique achieves a low detection limit for biomolecular interactions.
Area of Science:
- Biomolecular Interaction Analysis
- Optical Biosensing
- Nanotechnology
Background:
- Label-free optical biosensors are crucial for studying biomolecular interactions without labels.
- High throughput and low detection limits are essential for efficient biomolecule detection.
- The oblique-incidence reflectivity difference (OI-RD) technique excels at high-throughput detection of large biomolecules (>1000 Da).
Purpose of the Study:
- To enhance the detection capabilities of the OI-RD technique for small biomolecules (<500 Da).
- To develop a novel three-dimensional (3D) biochip for improved sensitivity and specificity.
- To achieve both high-throughput and low detection limits in biomolecular interaction analysis.
Main Methods:
- Development of a 3D biochip utilizing carboxymethyl chitosan (CMCS) functionalized slides.
- Optimization of immobilization parameters including sonication time, protein immobilization time, CMCS molecular weight, and glutaraldehyde (GA) functionalization time.
- Application of the optimized OI-RD technique for detecting small molecule interactions.
Main Results:
- Achieved a low detection limit of 6.8 pM for avidin (68 kDa).
- Successfully detected small molecules, including D-biotin (244 Da), demonstrating enhanced sensitivity.
- Validated the effectiveness of the CMCS-functionalized 3D biochip for OI-RD applications.
Conclusions:
- The developed 3D biochip significantly enhances the detection capability of the OI-RD technique for small biomolecules.
- This approach offers an effective solution for achieving high-throughput and low detection limits in biomolecular interaction studies.
- The findings pave the way for broader applications of OI-RD in sensitive and rapid biomolecular detection.
