AAT Bioquest

RatioWorks™ BCFL Acid *Superior replacement for BCECF*

The pH dependent absorbance spectra of BCFL Acid.
The pH dependent absorbance spectra of BCFL Acid.
The pH dependent absorbance spectra of BCFL Acid.
The pH dependent Emission spectra of BCFL Acid.
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Physical properties
Molecular weight~500
Spectral properties
Excitation (nm)504
Emission (nm)527
Storage, safety and handling
H-phraseH303, H313, H333
Hazard symbolXN
Intended useResearch Use Only (RUO)
R-phraseR20, R21, R22
StorageFreeze (< -15 °C); Minimize light exposure


Molecular weight
Excitation (nm)
Emission (nm)
Intracellular pH plays an important modulating role in many cellular events, including cell growth, calcium regulation, enzymatic activity, receptor-mediated signal transduction, ion transport, endocytosis, chemotaxis, cell adhesion and other cellular processes. pH-sensitive fluorescent dyes have been widely applied to monitor changes in intracellular pH in recent years. Imaging techniques that use fluorescent pH indicators also allow researchers to investigate these processes with much greater spatial resolution and sampling density that can be achieved using other technologies such as microelectrode. Among them, 2',7'-bis-(2-carboxyethyl)-5-(and-6)-carboxyfluorescein (BCECF) is the most popular pH probe since it can be used to monitor cellular pH ratiometrically. However, all the commercial BCECF AM is a complex mixture of at least three isomers with different ratios from batch to batch, complicating the BCECF applications. BCFL is developed to overcome this isomer difficulty associated with BCECF AM. As BCECF, BCFL exhibits a pH-dependent dual excitation, essentially identical to BCECF. It has pKa of ~7.0, identical to BCECF too. As with BCECF, the dual excitation spectrum of BCFL with an isosbestic point at 454 nm should make BCFL a good excitation-ratiometrie pH indicator. BCFL ratiometric imaging makes intracellular pH determination essentially independent of several variable factors, including dye concentration, path length, cellular leakage and photobleaching rate. BCFL, AM is a single isomer, making the pH measurement much more reproducible than the BCECF, AM, which is consisted of quite a few different isomers. This BCFL is the esterase-hydrolyzed product of BCFL AM that can be used a reference standard with BCFL AM.


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Spectral properties

Excitation (nm)504
Emission (nm)527

Product Family



View all 2 citations: Citation Explorer
The F0F1 ATP synthase regulates human neutrophil migration through cytoplasmic proton extrusion coupled with ATP generation
Authors: Gao, Jun and Zhang, Tian and Kang, Zhanfang and Ting, Weijen and Xu, Lingqing and Yin, Dazhong
Journal: Molecular Immunology (2017): 219--226
Oxidative Stress-Activated NHE1 Is Involved in High Glucose-Induced Apoptosis in Renal Tubular Epithelial Cells
Authors: Wu, Yiqing and Zhang, Min and Liu, Rui and Zhao, Chunjie
Journal: Yonsei Medical Journal (2016): 1252--1259


View all 34 references: Citation Explorer
Simultaneous measurement of water volume and pH in single cells using BCECF and fluorescence imaging microscopy
Authors: Alvarez-Leefmans FJ, Herrera-Perez JJ, Marquez MS, Blanco VM.
Journal: Biophys J (2006): 608
Photophysics of the fluorescent pH indicator BCECF
Authors: Boens N, Qin W, Basaric N, Orte A, Talavera EM, Alvarez-Pez JM.
Journal: J Phys Chem A Mol Spectrosc Kinet Environ Gen Theory (2006): 9334
Drug efflux transport properties of 2',7'-bis(2-carboxyethyl)-5(6)-carboxyfluorescein acetoxymethyl ester (bcecf-am) and its fluorescent free acid, bcecf
Authors: Bachmeier CJ, Trickler WJ, Miller DW.
Journal: J Pharm Sci (2004): 932
A rapid method for measuring intracellular pH using BCECF-AM
Authors: Ozkan P, Mutharasan R.
Journal: Biochim Biophys Acta (2002): 143
Detection of MRP functional activity: calcein AM but not BCECF AM as a Multidrug Resistance-related Protein (MRP1) substrate
Authors: Olson DP, Taylor BJ, Ivy SP.
Journal: Cytometry (2001): 105
Fluorescence probe (BCECF) loading efficiency in human platelets depends on cell concentration: application to pHi measurements
Authors: Ruiz-Palomo F, Garcia C, Gomez M, Revenga M.
Journal: Clin Biochem (1999): 391
In vivo application of intestinal ph measurement using 2',7'-bis(carboxyethyl)-5,6-carboxyfluorescein (bcecf) fluorescence imaging
Authors: Marechal X, Mordon S, Devoisselle JM, Begu S, Guery B, Neviere R, Buys B, Dhelin G, Lesage JC, Mathieu D, Chopin C.
Journal: Photochem Photobiol (1999): 813
Analysis of the uptake of the fluorescent marker 2',7'-bis-(2-carboxyethyl)-5(and-6)-carboxyfluorescein (bcecf) by hydrogenosomes in trichomonas vaginalis
Authors: Scott DA, Docampo R, Benchimol M.
Journal: Eur J Cell Biol (1998): 139
Simultaneous detection of cell volume and intracellular pH in isolated rat duodenal cells by confocal microscopy and BCECF
Authors: Weinlich M, Heydasch U, Mooren F, Starlinger M.
Journal: Res Exp Med (Berl) (1998): 73
BCECF in single cultured cells: inhomogeneous distribution but homogeneous response
Authors: Weinlich M, Theiss C, Lin CT, Kinne RK.
Journal: J Exp Biol (1998): 57