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An aptamer nanopore-enabled microsensor for detection of theophylline
Silu Feng1, Changtian Chen2, Wei Wang2
1Electrical and Computer Engineering Department, Iowa State University, USA.
Biosensors & Bioelectronics
|January 21, 2018
Summary
A novel aptamer-based nanopore sensor detects theophylline in complex samples with high sensitivity. This low-cost, reusable sensor is ideal for point-of-care theophylline monitoring.
Area of Science:
- Biosensing
- Nanotechnology
- Analytical Chemistry
Background:
- Antibody-based detection methods for theophylline are often costly and lack stability.
- There is a need for sensitive, specific, and rapid theophylline detection in various sample matrices.
- Nanopore thin film sensors offer potential for high-performance molecular detection.
Purpose of the Study:
- To develop and characterize an aptamer-based nanopore thin film sensor for theophylline detection.
- To evaluate the sensor's performance in buffer solutions and complex biological samples.
- To demonstrate the suitability of the sensor for point-of-care applications.
Main Methods:
- Fabrication of a nanopore thin film sensor functionalized with theophylline-specific aptamers.
- Electrochemical or electrical measurements to detect theophylline binding events.
- Testing sensor performance in buffer, plant extracts, and serum samples.
- Utilizing reference sensors to minimize non-specific binding effects.
Main Results:
- The aptamer-based sensor achieved a low detection limit of 0.05µM for theophylline.
- Demonstrated high specificity, selectivity, and reusability.
- Successfully detected theophylline in plant extracts and serum samples using minimal sample volume (~1μL).
- Outperformed traditional liquid chromatography (LC) in terms of detection limit.
Conclusions:
- Aptamer-based nanopore thin film sensors provide a sensitive and selective method for theophylline detection.
- The sensor's low cost, ease of operation, and minimal sample requirement make it suitable for point-of-care diagnostics.
- This technology enables real-time monitoring of theophylline levels in patients.
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