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A light-up fluorescence assay for tumor cell detection based on bifunctional split aptamers
Yuqiong Sun1, Baoyin Yuan, Meitao Deng
1State Key Laboratory of Chemo/Biosensing and Chemometrics, College of Chemistry and Chemical Engineering, College of Biology, Key Laboratory for Bio-Nanotechnology and Molecular Engineering of Hunan Province, Hunan University, Changsha 410082, China. kmwang@hnu.edu.cn yangxiaohai@hnu.edu.cn.
The Analyst
|July 13, 2018
Summary
This study introduces a novel light-up fluorescence assay for label-free tumor cell detection using bifunctional split aptamers (BFSA). The assay offers a sensitive, selective, and cost-effective method for identifying cancer cells in biological samples.
Area of Science:
- Biotechnology
- Molecular Biology
- Analytical Chemistry
Background:
- Light-up aptamers offer label-free detection with low background fluorescence.
- Existing methods for tumor cell detection can be complex and costly.
Purpose of the Study:
- To develop a novel light-up fluorescence assay for label-free tumor cell detection.
- To utilize bifunctional split aptamers (BFSA) for enhanced specificity and sensitivity.
Main Methods:
- Constructed a BFSA by combining aptamers ZY11 and ThT.2-2 for specific binding to SMMC-7721 tumor cells.
- Introduced a Helper strand to regulate the proximity of BFSA strands and thioflavin T (ThT) fluorescence activation.
- Utilized the 'induced-fit effect' for target cell-mediated signal generation.
Main Results:
- Achieved a linear response for tumor cell detection from 250 to 20,000 cells.
- Demonstrated a limit of detection as low as 125 cells.
- Showcased excellent selectivity and successful application in 20% human serum samples.
Conclusions:
- The developed BFSA assay provides a no-washing, label-free, one-step, and low-cost method for tumor cell detection.
- This aptamer probe design has potential applications in stimuli-responsive controlled drug delivery systems.
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