pH敏感荧光探剂BCECF

A pH-sensitive Fluorescein Dye BCECF

２’，７’－二（羧乙基）－５（６）－羧基荧光黄（ＢＣＥＣＦ）是一种新型的ｐＨ荧光探剂，它在４４０ｎｍ、４９０ｎｍ两处的荧光强度的比值（ＦＩＲ）与ｐＨ值相关。体外实验证明，ｐＨ值６．２０～７．８０范围内，ＦＩＲ与ｐＨ呈线形关系。用ＢＣＥＣＦ标记的蟾蜍膀胱上皮细胞，在ｐＨ值６．３０～７．７０范围内，细胞内ｐＨ（ｐＨｉ）与ＦＩＲ呈线性关系。用该法首次测得蟾蜍膀胱上皮细胞ｐＨｉ＝７．２１（ｎ＝８６）。

bis (carboxyethyl ) -5 (and 6) -carboxy- fluorescein (BCECF) is widely used as pH-sensitive fluorescein probe recently. When BCECF excites at 490mn and 440nm, the ratio of fluorescein intensities (FIR) using the two excitation wavelengths yields a pH-dependent parameter. As a result, FIR is a linear function of pH between pH value 6.20～7.80 ex vivo. Loading toad urinary bladder with BCECF, a similar linear function is resulted between pH value 6.30～7.70. The intracellular pH value of toad urinary bladder we first got is 7.21 (n=86).