Aptamer Sensor Based on Hybrid Chain Reaction and CRISPR-Cas9 System for STX Detection

Abstract

In recent years, pollution incidents caused by red tide occur frequently, and the red tide biotoxins brought by it make the food safety problem of seafood become a difficult problem to be solved urgently, which has caused great damage to the mariculture industry. Red tide toxin is also known as “shellfish toxin”. Saxitoxin (STX), is one of the strongest paralytic shellfish toxins and is also one of the most toxic marine toxins, which is extremely harmful. Aiming at the problems existing in the current research on the detection of red tide biotoxin in complex water bodies, this research developed an aptamer sensor based on hybrid chain reaction and a CRISPR-Cas9 gene editing system to detect the toxins of the clam and analyzed the feasibility of this method for the detection of the toxins of the clam. The results showed that the linear range of this method is 5.0 fM to 50 pM, and the detection limit is 1.2 fM. Meanwhile, the recovery rate of this sensor for the detection of toxins is 102.4–104.1% when applied in shellfish extract, which shows significant specificity and the reliability of this detection method.

Keywords

• hybrid chain reaction
• CRISPR-Cas9
• saxitoxin
• fluorescent detection