Aggregation induced emission (AIE) has attracted considerable interest for the development of fluorescence probes. However, controlling the bioconjugation and cellular labeling of AIE dots is a challenging problem. Here, this study reports a general approach for preparing small and bioconjugated AIE dots for specific labeling of cellular targets. The strategy is based on the synthesis of oxetane‐substituted AIEgens to generate compact and ultrastable AIE dots via photo‐crosslinking. A small amount of polymer enriched with oxetane groups is cocondensed with most of the AIEgens to functionalize the nanodot surface for subsequent streptavidin bioconjugation. Due to their small sizes, good stability, and surface functionalization, the cell‐surface markers and subcellular structures are specifically labeled by the AIE dot bioconjugates. Remarkably, stimulated emission depletion imaging with AIE dots is achieved for the first time, and the spatial resolution is significantly enhanced to ≈95 nm. This study provides a general approach for small functional molecules for preparing small sized and ultrastable nanodots.

中文翻译：

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面向紧凑纳米点的多色可光交联AIEgens用于亚细胞成像和STED纳米技术

聚集诱导发射（AIE）对于荧光探针的开发引起了相当大的兴趣。但是，控制AIE点的生物结合和细胞标记是一个具有挑战性的问题。在这里，这项研究报告了一种通用的方法，用于制备小的和生物共轭的AIE点，用于细胞靶标的特异性标记。该策略基于氧杂环丁烷取代的AIEgen的合成，以通过光交联产生紧密而超稳定的AIE点。少量富含氧杂环丁烷基的聚合物与大多数AIEgens共缩合，以使纳米点表面功能化，以用于随后的链霉亲和素生物缀合。由于它们的小尺寸，良好的稳定性和表面功能化，它们的细胞表面标记和亚细胞结构被AIE点生物缀合物特异性标记。值得注意的是 首次实现了具有AIE点的受激发射耗尽成像，并且空间分辨率显着提高到了约95 nm。这项研究为制备小尺寸和超稳定纳米点的小功能分子提供了一种通用方法。