Dicoumarol assisted synthesis of water dispersible gold nanoparticles for colorimetric sensing of cysteine and lysozyme in biofluids

摘要: The important roles of cysteine (Cys) and lysozyme (Lys) in biological systems have attracted great interest their detection various biofluids. Here, we report the use dicoumarol (DIC) as a novel reducing stabilizing agent for synthesis water-dispersible DIC-decorated gold nanoparticles (Au NPs) sensitive selective colorimetric determination Cys Lys characteristic surface plasmon resonance (SPR) peak at 525 nm solution color DIC–Au NPs undergo dramatic changes on exposure to Lys, yielding new absorption peaks appearing 666 570 concomitant change from cherry red blue purple respectively. high degree aggregation induced by was observed 0.4 M NaCl. Based this finding, propose method detect naked eye UV-visible spectrometry. proposed sensor quantitatively measured concentrations within dynamic range 10–90 μM (R2 = 0.9942) 100–800 nM 0.9961) with limits 2.2 × 10−6 8.7 10−9 This probe successfully applied human urine plasma egg white, demonstrating its value practical application systems.