Abstract

19-nortestosterone (19-NT), being regarded as the residual marker of banned synthetic steroid hormone nandrolone phenylpropionate, could cause adverse effects when consumed by human. To ensure food safety and minimize 19-NT toxicity, herein, an innovative electrochemical immunosensor for detection of 19-NT was constructed based on the modified polyvinyl alcohol/polyacrylic acid (PVA/PAA) nanofiber mat (NFM). The detection was achieved via a direct competition for binding to horse radish peroxidase-tagged anti-19-NT nanobody between free 19-NT and the 19-NT-ovalbumin covalently immobilized onto the NFM, and the amperometric response of immunosensor was analyzed using cyclic voltammetry. Under the optimal preparation conditions, the PVA/PAA NFM with appropriate hydrophilicity and ultra-high surface was obtained and characterized, and its electrochemical performance exhibited a 20-times increased response compared to the PVA/PAA casting membrane. The established immunosensor possessed high sensitivity towards 19-NT with a detection limit of 2.14 pg/mL, a 46-fold times lower compared to the traditional ic-ELISA of pure anti-19-NT nanobody. Recovery rates from the spiked animal urine samples ranged from 97.09 % to 117.32 %. Moreover, the sensor showed good reproducibility and stability over 6 weeks, suggesting that the nanofiber-based biosensor is a promising alternative for the fast and sensitive determination of 19-NT.

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.