Dojindo,BCECF/5/B031,BCECF 是细胞内 pH 探针

BCECF 是最广泛使用的细胞内 pH 探针。 Tsien 博士和其他人通过引入两种额外的羧酸盐来改进这种羧基荧光素,使其能够更好地被细胞保留。 BCECF 是高度水溶性的,因为它在中性 pH 下具有 4 至 5 个负电荷;加载后变得难以通过细胞膜。其 pKa 值为 6.97,高于羧基荧光素。 BCECF在激发光谱中在439 nm处有一个等吸收点,因此可用于比率测定,类似于Fura 2。比率测定通常使用505 nm和439 nm的波长,设置490 nm和450 nm滤光片在激发光源前。 530 nm 滤光片用于其荧光信号。请注意,激发光谱与吸收光谱略有不同。 BCECF-AM 是 BCECF 的乙酰氧基甲酯,可以轻松地将 BCECF 加载到细胞中。 BCECF-AM 与其他乙酰氧基甲酯一样,仅通过孵育才能在细胞中积累。 BCECF-AM 对水分非常敏感;应该小心处理。 DMSO 溶液的颜色随着 AM 形式的分解从淡黄色变为深橙色。因此,可以通过颜色变化来监测 AM 酯的水解。

Chemical Structure

General Protocol (for Human Neutrophil)*Reagents:– 1 mM BCECF-AM/DMSO solution (1 mg BCECF in 1.45 ml DMSO)– HEPES buffer saline (20 mM HEPES, 153 mM NaCl, 5 mM KCl, 5 mM glucose, pH 7.4)

Protocol:1. Suspend cells in HEPES buffer solution to prepare 4×107 cells per ml.2. Add 1 mM BCECF-AM/DMSO solution to the cell suspension to prepare 3 μM BCECF-AM (1/300 vol of cell suspension) as the final concentration.3. Incubate the cell suspension at 37ºC for 30 minutes.4. Wash the cells 3 times with HEPES buffer saline and then prepare 3×106 cells per ml of the cell suspension.5. Determine the fluorescence intensity using a fluorescence microscope or a confocal laser microscope coupled with an image analyzer.

* Cell staining conditions depend on cell type, so it is necessary to optimize the conditions for each experiment

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