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C85778

Sigma-Aldrich

o-Cresolphthalein

Indicator grade, powder

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About This Item

Empirical Formula (Hill Notation):
C22H18O4
CAS Number:
Molecular Weight:
346.38
Beilstein:
310554
EC Number:
MDL number:
UNSPSC Code:
12171500
PubChem Substance ID:
NACRES:
NA.47

product name

o-Cresolphthalein, indicator grade

grade

indicator grade

form

powder

technique(s)

titration: suitable

color

beige

pH

8.2-9.8, colorless to red

mp

219-221 °C (lit.)

λmax

381 nm (2nd)
566 nm

ε (extinction coefficient)

≥10000 at 294-300 nm
≥39000 at 564-570 nm
≥5000 at 378-384 nm

application(s)

diagnostic assay manufacturing
hematology
histology

storage temp.

room temp

SMILES string

Cc1cc(ccc1O)C2(OC(=O)c3ccccc23)c4ccc(O)c(C)c4

InChI

1S/C22H18O4/c1-13-11-15(7-9-19(13)23)22(16-8-10-20(24)14(2)12-16)18-6-4-3-5-17(18)21(25)26-22/h3-12,23-24H,1-2H3

InChI key

CPBJMKMKNCRKQB-UHFFFAOYSA-N

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Application

O-Cresolphthalein has been used as a component in calcifying media for calcification assay.

Biochem/physiol Actions

o-Cresolphthalein is a reversible pH indicator. The kinetics of the reverse pathway (red-purple to colorless) is slow, thereby making it an appropriate molecule to check flow patterns in ducts with corrugated walls. It is also used for the colorimetric determination of calcium content via the o-cresolphthalein complexone method. Binding of calcium to o-cresolphthalein, in the presence of alkaline conditions (pH 10-12), results in the formation of a red complex with an absorbance at 570-575nm.

Storage Class Code

11 - Combustible Solids

WGK

WGK 3

Flash Point(F)

Not applicable

Flash Point(C)

Not applicable

Personal Protective Equipment

dust mask type N95 (US), Eyeshields, Gloves

Certificates of Analysis (COA)

Search for Certificates of Analysis (COA) by entering the products Lot/Batch Number. Lot and Batch Numbers can be found on a product’s label following the words ‘Lot’ or ‘Batch’.

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Natalia Campos-Obando et al.
European journal of epidemiology (2018-05-17)
Hyperphosphatemia has been associated with increased mortality in chronic kidney disease but the nature of such a relation in the general population is unclear. To investigate the association between phosphate (P) levels and all-cause and cause-specific mortality, we assessed two
Jin-Hyun Kim et al.
PloS one, 14(4), e0215244-e0215244 (2019-04-17)
In the stratum corneum, the intercellular junction made up of cadherin proteins provides the structural integrity of the framework. Ca2+ ions are known to play a key role in maintaining this junction. In this study, we hypothesized that Ca2+ chelation
Hyunseok Peter Kang et al.
Clinical chemistry, 50(4), 741-746 (2004-02-14)
Gadolinium formulations, which are administered as contrast agents in magnetic resonance imaging examinations, interfere with colorimetric serum calcium determinations. We performed an in vitro study to determine the extent to which three gadolinium formulations-gadodiamide (Omniscan), gadopentetate dimeglumine (Magnevist), and gadoversetamide
Ali Duran et al.
Journal of hazardous materials, 169(1-3), 466-471 (2009-04-29)
In present study preconcentration followed by solid phase extraction of heavy metal ions, Cu(II), Co(II), Ni(II) and Pb(II) using a multiwalled carbon nanotubes (MWNTs) and complexing reagent o-cresolphthalein complexone were investigated. The effects of parameters, including pH of the solutions
P Sótonyi et al.
Histochemistry, 75(3), 425-436 (1982-01-01)
The ortho-cresolphtalein complex was successfully adapted for the electron microscopic cytochemical demonstration of calcium. The reaction product is of granular nature with sufficient electron density for finer localization. Intense precipitation was found on the sarcolemma and transverse tubules and in

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