Phage-Mediated Immuno-PCR for Ultrasensitive Detection of CrylAc Protein Based on Nanobody

摘要

The widespread use of Cry proteins in transgenic plants for insect control has raised concerns about the environment and food safety in the public. An effective detection method for introduced Cry proteins is of significance for environmental risk assessment and product quality control. This paper describes a novel phage mediated immuno-PCR (iPCR) for the ultrasensitive determination of Cry proteins based on nanobodies. Three nanobodies against CrylAc protein were obtained from a na ve phage displayed nanobody library without animal immunization process and were applied to the iPCR assay for CrylAc. The phage-mediated iPCR for CrylAc based on nanobodies showed a dynamic range of 0.001-100 ng/mL and a limit detection of 0.1 pg/mL. Specific measurement of this established method was performed by testing cross-reativity of other CrylAc analogues, and the result showed negligible cross-reactivity with other test Cry proteins (CrylAb, Cry1F, Cry3B). Furthermore, the phage-mediated iPCR based on nanobody should be easily applicable to the detection of many other Cry proteins.