Eriochrome cyanine R (C.I. 43820, Mordant blue 3), also known as chromoxane cyanine R and solochrome cyanine R, has been used as a biological stain since 1957. In conjunction with ferric ions, it provides selective blue coloration of the nuclei of cells in methods procedurally similar to commonly used progressive or regressive hemalum (aluminum-hematoxylin) stains. Eriochrome cyanine R also is used to stain the myelin sheaths of axons in nerve tissue; the results are visually similar to those in sections stained with luxol fast blue MBS (C.I. 74180, solvent blue 38) with selective blue coloration of myelin and erythrocytes. Eriochrome cyanine R is an article of commerce with many uses in industrial coloration and analytical chemistry; it can be used instead of either hematoxylin or luxol fast blue MBS, especially in the event of a shortage of either of the latter compounds. The Biological Stain Commission (BSC) will certify batches of eriochrome cyanine R that meet the criteria set out in this document. The criteria include satisfactory UV/visible spectra at pH 4 and pH 12 − 13, a dye content not less than 40% and not greater than 52% (calculated as the color acid; equivalent to 46 − 59% of the trisodium salt), and satisfactory performance in three staining methods: regressive for nuclei, progressive for nuclei and regressive for myelin.

自1957年以来，Eriochrome cyanine R（CI 43820，媒染剂蓝3），也称为chromoxane cyanine R和solochrome cyanine R，已被用作生物染色剂。与三价铁离子结合使用，可为细胞中的细胞核提供选择性的蓝色着色。程序上的方法与常用的渐进或渐进式血尿素（铝-苏木精）染色相似。Eriochrome cyanine R也用于染色神经组织中轴突的髓鞘。结果在视觉上类似于用luxol坚牢蓝MBS（CI 74180，溶剂蓝38）染色的部分，髓鞘和红细胞具有选择性的蓝色。Eriochrome cyanine R是一种商品，在工业着色和分析化学中有许多用途。它可以代替苏木素或luxol固蓝MBS来使用，特别是在缺少后一种化合物的情况下。生物染色委员会（BSC）将对符合本文件规定标准的一批铬铬花菁R进行认证。标准包括在pH 4和pH 12-13时令人满意的UV /可见光谱，染料含量不小于40％且不大于52％（以色酸计；相当于三钠盐的46-59％），在三种染色方法中均具有令人满意的性能：细胞核退变，细胞核渐进和髓磷脂退变。