Complementary DNA Significantly Enhancing Signal Response and Sensitivity of a Molecular Beacon Probe to Aflatoxin B1

Area of Science:

• Analytical Chemistry
• Biotechnology
• Food Safety

Background:

• Aflatoxin B1 (AFB1) is a highly carcinogenic mycotoxin found naturally in food.
• Sensitive and rapid detection methods for AFB1 are crucial for public health and food safety.
• Existing detection methods may lack sufficient sensitivity or speed.

Purpose of the Study:

• To develop an improved molecular beacon method for the rapid and sensitive detection of aflatoxin B1 (AFB1).
• To enhance the fluorescent response of a DNA aptamer-based molecular beacon using a complementary DNA (cDNA) chain.
• To optimize experimental factors for rapid AFB1 detection within a clinically relevant timeframe.

Main Methods:

• Utilized a DNA aptamer-based molecular beacon system functionalized with FAM and BHQ1.
• Incorporated a complementary DNA (cDNA) chain to amplify the fluorescent signal.
• Optimized key experimental parameters to achieve rapid detection.
• Validated the method for specificity and anti-interference capabilities.

Main Results:

• Achieved a significantly larger fluorescent response to AFB1 with cDNA assistance.
• Enabled rapid detection of AFB1 in the range of 1 nM to 3 μM within 20 minutes.
• Obtained a limit of detection (LoD) of 1 nM, which is lower than the 8 nM LoD without cDNA.
• Demonstrated good specificity and anti-interference properties.

Conclusions:

• The improved molecular beacon method offers a sensitive, rapid, and user-friendly approach for AFB1 detection.
• The use of cDNA significantly enhances the performance of the aptamer-based molecular beacon.
• This method shows strong potential for application in real-world food safety analysis.