Authors: T. Tohidi Moghadam and B. Ranjbar
Affilation: Tarbiat Modares university, Iran, Islamic Republic of
Pages: 192 - 195
Keywords: gold nanorods, surface plasmon resonance, aptamer
Gold nanorods (GNRs) have been nominated as good candidates for biosensing, diagnostics, and imaging technologies. The wavelength dependence of the longitudinal surface plasmon resonance of gold nanorods on minute changes of refractive indexes makes them extremely sensitive reporters of molecular binding events with excellent multiplexing capability. Herein, aptamer functionalized GNRs were used for calorimetric detection of lysozyme, since excretion of elevated levels of lysozyme in urine could be a sign of kidney’s tubular cell damage and Acute myelomonocytic leukemia. Gold nanorods were synthesised and characterized by UV-Vis and TEM.Purified GNRs were covalently conjugated with thiolated lysozyme aptamer and analyzed by FTIR. The nanobiosensor started to develop clear LSPR shifts and distinct change of colour at various concentrations of biomolecule. Presence of target biomolecule dictated specific aggregation of GNRs. The aggregation phenomenon was also characterized by UV-Visible and TEM. Target binding was monitored in control experiments with BSA, normal blood serum, and positive acute myeloid leukemia, which showed good specificity for lysozyme detection. Quantitative analysis of the biosensor by tracing LSPR responses indicated sensitivity of the nanobiosensor down to pico molar level. This investigation encourages utilization of GNRs for fabrication of a new generation of diagnostic technique based on gold nanotechnology.