o-Cresolphthalein excellent quality manufacturer, exporter and supplier. o-Cresolphthalein is a pH indicator used in titrations. It is insoluble in water but soluble in ethanol. Its solution is colourless below pH 8.2, and purple above 9.8. It is also used for the colorimetric determination of calcium content via the o-cresolphthalein complexone method. 

Technical Specifications:
C.A.S. No. 596-27-0
M.F. C22H18O4
M.W. 346.38gm/mole


Dye Content (by Spectrophotometry) >95%
Appearance White-Off white powder
Solubility 0.1% (EtOH) Clear solution
Transition Range pH 8.2-9.8
Absorption maximum (0.1N NaOH) at ?max 564-568nm
Absorptivity (A1%1cm in 0.1N NaOH at ?max) >1670
Loss On Drying (110°C) <1%

Synonym: o-Cresolphthalein-3%u2032,3%u2032%u2032-bis-methyleneiminodiacetic acid, o-Cresolphthalexon, Metal phthalein, Phthalein purple, Xylenylphthalein-bisiminodiacetic acid

Using Procedure:

This MC-Reagent Calcium Assay Kit is a direct colorimetric assay based on the O-Cresolphtalein (OCPC) method without deproteinization of the sample. The calcium determination is based on the reaction of calcium with O-Cresolphthalein complexone in alkaline solution, which yields a violet colored complex. The intensity of the color formed is proportional to the calcium concentration in the sample. Absorbance of the Ca2+-O-Cresolphtalein complex is measured at 570nm. Wavelength range of sensitivity: 560 ~ 590nm.


Features of this Assay: Quick & Easy to use %u2022 Species independent %u2022 Highly sensitive, stable and suitable for high-throughput testing %u2022 No toxic substances %u2022 For cell lysates, serum, plasma and wide variety of biological samples

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