Lab in tube: comparing different morphological dependent gold nanomaterials towards naked eye and optical sensing of dopamine using aptamer

Abstract

ABSTRACT Dopamine is a major catecholamine neuro-transmitter that plays important function in the human central nervous system’s function. Dopamine release disorders are linked to neurological illnesses and depression. To comprehend dopamine’s physiological roles, it is vital to monitor dopamine levels at early stage or in regular basis. Many diagnostic procedures are accessible, but they have limitations, thus low-cost and simple ways to test dopamine were needed like colorimetric biosensors. Such biosensors were built with nanoparticles (gold) as a label to help identify targets and the results may be viewed with the naked eye. These gold nanomaterials are available in a range of morphologies, including nanoparticles, nanorods, and others. The present method reported the use of gold nanoparticles (GNPs) and gold nanorods (GNRs) for effective aptamer-based sensing of dopamine. Herein a comparison study was conducted between GNPs and GNRs based apta-sensing of dopamine. Both AuNPs (gold nanoparticles) and AuNRs (gold nanorods) were characterised by SEM (Scanning electron microscope), XRD (X-Ray diffraction) and UV-Vis spectrophotometer (Ultraviolet-Visible spectroscopy). The result claimed that GNRs are more sensitive as they were detecting low concentration of dopamine which was confirmed via UV analysis. Various other parameters such as change in salt concentration, incubation time and interferents were also studied which proved that utilising aptamer and gold-nanorods can be a promising material in the neurotransmitter based diagnosis.