Carboxyl functionalized gold nanorods for sensitive visual detection of biomolecules

• DOI: 10.1016/j.bios.2020.112324
• Publication Date: 2020-05-30T10:23:27Z
• Authors: Friedrich Scholz; Lukas Rüttinger; Theresa Heckmann; Lisa Freund; Anne-Marie Gad; Tobias Fischer; Andreas Gütter; Hans Hermann Söffing
• Keywords: C-Reactive Protein; Nanotubes; Metal Nanoparticles; Biosensing Techniques; Gold; Surface Plasmon Resonance; 01 natural sciences; 0104 chemical sciences

Antibody-modified gold nanomaterials are central to many novel biosensing technologies for example the lateral flow assays technology. The combination of the specificity, provided by antibody-antigen interactions, and the unique optical properties of nanomaterials provide excellent properties for biosensors. Here, we present the use of gold nanorods (GNR) with the localized Surface Plasmon Resonance (LSPR) peak in the visible range for biomarker detection. The colour of the GNR can be tuned by the reaction conditions to provide multi-coloured gold nanorod conjugates. These antibody functionalized GNR have the potential to provide significant improvements in multiplexed analysis and sensitivity compared to conventional gold nanoparticle based lateral flow assays. However, a major challenge is the synthesis of stable conjugates that resist aggregation in samples with high ionic strength, (e.g. salt solutions) and allow highly sensitive detection of proteins. A detailed investigation of different reagents for the functionalization of gold nanorod materials are reported. An antibody modified GNR based lateral flow assay is validated for the determination of C-reactive Protein (CRP).