Functionalization of Gold Nanostars with Melamine for Colorimetric Detection of Uric Acid

Gold nanostars (AuNSs) are synthesized using a seed-mediated growth method. The synthesized AuNSs solution is stable and shows a localized surface plasmon resonance (LSPR) band in the visible range, which is confirmed using ultraviolet-visible (UV-Vis) spectroscopy. Furthermore, the as-synthesized AuNSs were functionalized with melamine and used as a sensor for the colorimetric detection of uric acid (UA). The detection mechanism could be assessed through various analytical techniques such as UV-Vis spectroscopy, Fourier transform infrared (FT-IR) spectroscopy, dynamic light scattering (DLS), zeta potential, field emission scanning electron microscopy (FE-SEM), and transmission electron microscopic techniques. These methods exhibited a good linear regression between the absorption ratio of LSPR band of melamine-AuNSs and the concentration of UA (0-120 mu M), with the detection limit of 8.50 nm. As a result, UA was quantitatively detected in biofluids by using melamine-AuNSs as a colorimetric sensor, revealing melamine-AuNSs-based colorimetric approach which could be used as a simple platform for UA assay in biofluids.

Automated summary

Gold nanostars (AuNSs) were synthesized using a seed-mediated growth method, and their stability and localized surface plasmon resonance (LSPR) band were confirmed through UV-Vis spectroscopy. The as-synthesized AuNSs were functionalized with melamine and used as a colorimetric sensor for the detection of uric acid (UA). Various analytical techniques demonstrated a good linear regression between the absorption ratio of LSPR band of melamine-AuNSs and the concentration of UA, with a detection limit of 8.50 nm. Therefore, melamine-AuNSs-based colorimetric approach provides a simple platform for quantitative detection of UA in biofluids.