Lateral flow tests are widely used in clinical and non-clinical applications for detection of analytes in complex sample matrix.
However, a need for multiplex, ultra-sensitive, diagnostic assay providing quantitative results is inevitable. A label-free,
multi-analyte lateral flow test strip using gold nanorods is being developed for rapid and simultaneous quantification of
disease representing biomarkers in their clinically relevant ranges. Gold nanoparticles exhibit a strong optical extinction
at visible and near infrared wavelengths due to localized surface plasmon resonance (SPR). The band can be tuned by increasing
the aspect ratio of the nanorod, which is suitable for multiplex biosensing. Monodispersed gold nanorods of various aspect
ratios (e.g. 5, 10) were synthesized by seed mediated growth method and characterized using electron microscopy. Biofunctionalization
of the nanorods and immobilization of nanorod probes were investigated. The test region in the strip has multiple capture
lines embedded with functional biomolecules for quantitative assessment. As a model system, HER2 level in the clinical significant
range is assayed for early stage appraisal of breast cancer.
Keywords SPR - Gold nanorods - Lateral flow test strips