Epoxy-embedded semithin sections are useful for the analysis of cell and tissue organization, as well as for the processing of samples for transmission electron microscopy. Because only a very limited number of staining protocols have been developed for epoxy-embedded sections; semithin sections are used infrequently compared to conventional paraffin sections. Here, we describe a simple and reproducible polychromatic protocol for the routine staining of epoxy-embedded semithin sections by adapting Twort's staining method (mixture of neutral red and fast green FCF). The method can be used for the visualization of cellular organization as well as for the detection of elastic and collagen fibers. The proposed protocol demonstrated the best results for samples fixed for transmission electron microscopy, which suggests, as we demonstrated here, that this staining protocol can also be used for correlative light and electron microscopy.

中文翻译：

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改进的Twort方法对环氧包埋的半薄切片进行多色染色。

环氧树脂包埋的半薄切片可用于分析细胞和组织的组织，以及用于透射电子显微镜检查样品的处理。因为仅对环氧树脂包埋的部分开发了非常有限的染色方案，所以 与常规石蜡切片相比，半薄切片很少使用。在这里，我们描述了一种简单且可重现的多色协议，该协议通过采用Twort染色方法（中性红色和快绿色FCF的混合物）对环氧树脂包埋的半薄切片进行常规染色。该方法可用于细胞组织的可视化以及弹性和胶原纤维的检测。拟议的方案证明了固定用于透射电子显微镜的样品的最佳结果，这表明，正如我们在此处证明的那样，