Dopamine (DA) is a monoamine neurotransmitter of phenethylamine and catecholamine families, which is present in the central nervous system (CNS) and its periphery. Since DA is associated with several functions in the brain and body (motivational salience, reward, motor control, paracrine messenger, etc.), any imbalance in the DA level can trigger several neurodegenerative and other diseases. On the other hand, the spherical gold nanoparticles (AuNPs) can be used for drug delivery in several parts of the body. In addition, AuNPs also have the potentiality to penetrate through the blood-brain barrier and interact with the central nervous system without causing any toxicity. In view of many applications, it is important to look into the interaction between DA and AuNPs for a potential drug delivery model in DA related diseases. Here, we have used the steady-state and time-resolved fluorescence spectroscopic tools to investigate the binding interaction of DA with AuNPs. The nature of the quenching mechanism was confirmed through both steady-state and time-resolved fluorescence measurements. The binding constants along with the number of binding sites were estimated from the steady-state fluorescence measurements. The distance between DA and AuNPs was calculated using Förster's theory to verify the possibility of fluorescence resonance energy transfer (FRET) from DA to AuNPs.

中文翻译：

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多巴胺与球形金纳米粒子相互作用的光谱学见解。

多巴胺（DA）是苯乙胺和儿茶酚胺家族的单胺神经递质，存在于中枢神经系统（CNS）及其周围。由于DA与大脑和身体的多种功能（动机显着，奖励，运动控制，旁分泌信使等）相关，因此DA水平的任何失衡都会引发多种神经退行性疾病和其他疾病。另一方面，球形金纳米颗粒（AuNPs）可用于在身体的多个部位进行药物输送。此外，AuNPs还具有穿透血脑屏障并与中枢神经系统相互作用而不会引起任何毒性的潜力。鉴于许多应用，重要的是研究DA和AuNP之间的相互作用，以用于DA相关疾病中的潜在药物递送模型。这里，我们已经使用稳态和时间分辨荧光光谱工具研究了DA与AuNPs的结合相互作用。通过稳态和时间分辨荧光测量证实了淬灭机理的性质。从稳态荧光测量值估计结合常数以及结合位点的数目。DA和AuNPs之间的距离是使用Förster理论计算的，以验证从DA到AuNPs的荧光共振能量转移（FRET）的可能性。从稳态荧光测量值估计结合常数以及结合位点的数目。DA和AuNPs之间的距离是使用Förster理论计算的，以验证从DA到AuNPs的荧光共振能量转移（FRET）的可能性。从稳态荧光测量值估计结合常数以及结合位点的数目。DA和AuNPs之间的距离是使用Förster理论计算的，以验证从DA到AuNPs的荧光共振能量转移（FRET）的可能性。