Rational Design of Thiolated Polyenes as Trifunctional Raman Reporter Molecules in SERS Nanotags for Cytokine Detection in a Lateral Flow Assay.
The characteristic vibrational spectroscopic fingerprint of Raman reporter molecules adsorbed on noble metal nanoparticles is employed for the identification of target proteins by the corresponding SERS nanotag labeled antibodies. Here, we present the modular synthesis of thiolated polyenes with two to five C=C double bonds introduced via stepwise Wittig reactions. The experimental characterization of their electronic and vibrational properties is complemented by density functional theory (DFT) calculations. Highly SERS active nanotags are generated by using the thiolated polyenes as Raman reporter molecules in Au/Au core/satellite supraparticles with multiple hot spots. The cytokines IL 1b and IFN g are detected in a duplex SERS based lateral flow assay (LFA) on a nitrocellulose test strip by Raman microscopy. The thiolated polyenes are suitable for use in immuno SERS (iSERS) applications such as point of care testing (POCT) as well as cellular and tissue imaging. This article is protected by copyright. All rights reserved.
Journal of biophotonics