Microfluidic flow-injection aptamer-based chemiluminescence platform for sulfadimethoxine detection

Area of Science:

• Nanomaterials Science
• Analytical Chemistry
• Biotechnology

Background:

• Gold nanoparticle (AuNP) aggregation enhances luminol chemiluminescence (CL), providing a signal amplification strategy.
• Disruption of AuNP aggregation by analytes allows for sensitive signal-based detection.
• Aptamer-based assays offer high specificity and stability for analyte recognition.

Purpose of the Study:

• To develop a homogeneous aptamer-based assay for sulfadimethoxine (SDM) detection using a microfluidic CL platform.
• To investigate and optimize microfluidic mixer designs (2D vs. 3D) for efficient reagent mixing.
• To evaluate luminol derivatives for enhanced CL signal and assay performance.

Main Methods:

• Fabrication and testing of 2D and 3D microfluidic mixers using Xurography.
• Optimization of a 5-layer laminated 3D microfluidic mixer for improved mixing and CCD imaging.
• Comparative study of luminol and m-carboxy luminol for CL signal enhancement.
• Development of an aptamer-based assay for SDM detection on the optimized platform.

Main Results:

• A 3D 5-layer microfluidic mixer significantly improved mixing efficiency compared to 2D designs.
• M-carboxy luminol provided a tenfold signal enhancement over standard luminol.
• The aptamer-based assay achieved a wide dynamic range (0.01–1000 ng/ml) for SDM detection.
• A low limit of detection (LOD) of 4 pg/ml for SDM was obtained.

Conclusions:

• The developed microfluidic CL platform enables rapid, sensitive, and specific detection of SDM.
• This approach offers a cost-effective alternative to enzyme-based assays for analyte detection.
• The platform is suitable for real-time analysis in environmental monitoring and food safety applications.