用于碱性磷酸酶标记分子的比色检测，可使用5-溴-4-氯-3-吲哚基磷酸酯（BCIP）和硝基蓝四唑（NBT）。BCIP/NBT底物系统具有多种功能并用于多种应用，包括Northern Southern和Western blotting、原位杂交和免疫组化。BCIP以两种盐形式提供：可溶于水的二钠盐和可溶于二甲基甲酰胺的对甲苯胺形式。这些盐形式可用于制备与NBT及反应缓冲液组合的储存溶液，并形成碱性磷酸酶的底物溶液。当与碱性磷酸酶一起孵育时，该底物系统可产生不溶的NBT二甲嗪产物，具有容易被观察到的紫色。为了方便起见，BCIP和NBT的混合物是以一种易溶解的片剂形式或作为即用型液体而提供的。 For the colorimetric detection of alkaline phosphatase-labeled molecules, 5-Bromo-4-chloro-3-indolyl phosphate (BCIP) and Nitro Blue Tetrazolium (NBT) are available. The BCIP/NBT substrate system is versatile and functions in a variety of applications, including Northern Southern, and Western blotting, in situ hybridization, and immunohistochemistry. BCIP is provided in two salt forms: the disodium salt which is soluble in water and the p-toluidine form which is soluble in dimethylformamide. These salt forms may be used to prepare a stock solution that in combination with NBT and a reaction buffer, form a substrate solution for alkaline phosphatase. This substrate system, when incubated with alkaline phosphatase, produces an insoluble NBT diformazan product that is easily observable with its purple color. For added convenience, a mixture of BCIP and NBT is provided in an easily dissolvable tablet form or as a ready-to-use liquid.