An ultrasensitive and specific fluorescence split-aptasensor for VEGF 165 detection based on nicking enzyme-assisted 3D DNA walker coupling with CRISPR-Cas12a.

The overexpression of vascular endothelial growth factor 165 (VEGF ₁₆₅ ) in cancer cells plays a pivotal role in promoting tumor metastasis by facilitating their excessively rapid proliferation and division. Hence, the development of analytical methods possessing high sensitivity and resistance to interference is imperative for the detection of VEGF ₁₆₅ . Various types of aptasensors have been devised for VEGF ₁₆₅ detection; however, the performance of these biosensors can be influenced by non-target signals caused by conformational changes in unbound aptamers. The paper shows the creation of a precise and sensitive fluorescence biosensor designed to detect VEGF ₁₆₅ by using a VEGF ₁₆₅ -specific split aptamer. Additionally, this biosensor employs nicking enzyme-assisted DNA walker coupling with CRISPR-Cas12a to achieve dual-signal amplification. The VEGF ₁₆₅ calibration curve shows a detection limit of 268 fM and has a broad linear range from 5 to 4000 nM. The fluorometric biosensor was utilized to detect VEGF ₁₆₅ in human serum and cellular homogenate samples, yielding good outcomes. The innovative design serves as proof of concept and demonstrates significant potential in detecting various targets.
Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.
(Copyright © 2024 Elsevier B.V. All rights reserved.)