As luminescent quantum dots (QDs) are known to aggregate themselves through their chemical activation by carbodiimide chemistry and their functionalization with biotin molecules, we investigate both effects on the fluorescence properties of CdTe QDs and their impact on Förster Resonant Energy Transfer (FRET) occurring with fluorescent streptavidin molecules (FA). First, the QDs fluorescence spectrum undergoes significant changes during the activation step which are explained thanks to an original analytical model based on QDs intra‐aggregate screening and inter‐QDs FRET. We also highlight the strong influence of biotin in solution on FRET efficiency, and define the experimental conditions maximizing the FRET. Finally, a free‐QD‐based system and an aggregated‐QD‐based system are studied in order to compare their detection threshold. The results show a minimum concentration limit of 80 nM in FA for the former while it is equal to 5 nM for the latter, favouring monitored aggregation in the design of QDs‐based biosensors.

中文翻译：

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量子点聚集如何增强Förster共振能量传递。

由于已知发光量子点（QD）通过碳二亚胺化学作用进行化学活化及其与生物素分子的功能化而聚集在一起，因此我们研究了对CdTe QD荧光性质的影响以及它们对伴随发生的Förster共振能量转移（FRET）的影响。荧光链霉亲和素分子（FA）。首先，量子点的荧光光谱在激活步骤中发生了显着变化，这要归功于基于量子点内部聚集筛选和量子点间FRET的原始分析模型。我们还强调了溶液中生物素对FRET效率的强大影响，并定义了使FRET最大化的实验条件。最后，研究了基于自由QD的系统和基于聚集QD的系统，以比较它们的检测阈值。