Ratiometric Fluorescence Detection of Tyrosinase Activity and Dopamine Using Thiolate-Protected Gold Nanoclusters

Abstract

In this work, a sensitive and selective ratiometric fluorescence sensing platform was built for the detection of tyrosinase (TYR) activity and dopamine (DA) using glutathione (GSH) protected gold nanoclusters (Au NCs) as probes. Upon excitation at 350 nm, Au NCs displayed an intense red emission, which could be effectively quenched by quinones. TYR, a typical polyphenol oxidase, can catalyze the oxidization of DA to o-quinone and therefore quenched the fluorescence of Au NCs. Moreover, the reaction of TYR and DA gave rise to an emission band at 400 nm, which increased in a TYR/DA-concentration-dependent manner. The ratiometric signal variations were utilized for facile, sensitive, and selective detection of TYR activity and DA. A linear range was obtained from 0.006-3.6 unit mL(-1) of TYR activity, while the linear range for detection of DA was 1.0 nM to 1.0 mM. Additionally, it constructed a useful platform for TYR inhibitor screening in biomedical research.

Rapid determination of dopamine in human plasma using a gold nanoparticle-based dual-mode sensing system

“…The color variation of AuNPs associated with the reversible process from dispersion to aggregation induced by the intermolecular interactions between dopamine and surface modifiers on the AuNPs can be observed by naked eyes and quantified by UV-vis spectra [18][19][20][21][22]. In addition, several fluorometric assays have been demonstrated for the detection of dopamine with high sensitivity using fluorophores such as calcein blue-Fe 2+ complex [23], carbon dots [24], silicon nanoparticles [25], molecule capped QDs [26][27][28][29], and gold nanoclusters (AuNCs) [30,31]. To the best of our knowledge, only one dual-mode assay has been reported for dopamine detection, where BSA-stabilized AuNCs were employed as sensing components [32].…”

Fluorescent Gold Nanoclusters: Promising Fluorescent Probes for Sensors and Bioimaging

“…A ratiometric fluorescence sensing platform was developed by Wang's group for DA detection by using GSH-protected AuNCs as probes. The obtained linear range was 1.0 nM-1.0 mM [90]. More recently, Yun's group reported stable, nontoxic, and red fluorescent BSA-Au NCs for selective detection of DA in cerebrospinal fluid [91].…”

Voltammetric dopamine sensor based on three-dimensional electrosynthesized molecularly imprinted polymers and polypyrrole nanowires

“…Therefore, accurate determination of DA in biological fluids are crucial to trace and diagnose diseases. Over the past few decades, researchers have studied the in vivo monitoring of the concentration of dopamine in environmental and biological samples, such as highperformance liquid chromatography [4,5], fluorescence spectrophotometry [6,7], and electrochemical methods [8,9]. Among them, the electrochemical method possesses a series of advantages including rapid response, low cost, simple operation and sensitivity.…”