A sensitive fluorescent analytical method for the detection of dopamine (DA) was developed based on surface-enhanced Tb(III)/La(III) co-luminescence using silver nanoflowers (AgNFs). Anisotropic AgNFs show strong surface-enhanced fluorescence effect owing to the abundant sharp tips. Tb(III)/La(III)-DA complexes mainly bind to the sharp tips of AgNFs and thus shorten the distance between the complexes. The shortened distance gives rise to obvious surface-enhanced Tb(III)/La(III) co-luminescence effect. In this work, AgNFs offer many superior properties, such as enhanced intrinsic green fluorescence of Tb(III) (λ_ex/λ_em = 310/546 nm), increased fluorescence lifetime, and improved energy transfer efficiency. Under the optimum conditions, the fluorescence intensity is linearly correlated with the concentration of DA in the range of 0.80–10 nM (R² = 0.9970), and the detection limit is 0.34 nM (S/N = 3). The fluorescent nanoprobe was successfully applied to the determination of DA in human serum samples with recoveries ranging from 99.1 to 102.6%.

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基于银纳米花（AgNFs）的表面增强的Tb（III）/ La（III）共发光，开发了一种用于检测多巴胺（DA）的灵敏荧光分析方法。由于具有丰富的尖锐尖端，各向异性的AgNFs具有很强的表面增强荧光作用。Tb（III）/ La（III）-DA复合物主要与AgNFs的尖端结合，因此缩短了复合物之间的距离。缩短的距离会产生明显的表面增强的Tb（III）/ La（III）共发光效应。在这项工作中，AgNFs提供了许多优异性能，如铽（III）的增强固有绿色荧光（λ _EX / λ _EM = 310/546 nm），延长的荧光寿命和提高的能量转移效率。在最佳条件下，荧光强度与DA的浓度在0.80–10 nM（R ²  = 0.9970）范围内线性相关，检出限为0.34 nM（S / N  = 3）。荧光纳米探针已成功应用于人血清样品中DA的测定，回收率在99.1至102.6％之间。

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