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F9252

Sigma-Aldrich

Folin & Ciocalteu′s phenol reagent

suitable for determination of total protein by Lowry method, 1.9-2.1 N

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About This Item

MDL number:
MFCD00132625
UNSPSC Code:
12171500
NACRES:
NA.47

form

liquid

Quality Level

200

concentration

1.9-2.1 N

color

clear yellow
faint yellow to very dark yellow, and Faint Green-Yellow to Very Dark Green-Yellow

pH

<0.5 (20 °C)

density

1.240 g/cm3 at 20 °C

suitability

suitable for determination of total protein by Lowry method

application(s)

diagnostic assay manufacturing
hematology
histology

storage temp.

room temp

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General description

Folin & Ciocalteu′s phenol reagent is most commonly used in the Lowry method for determining protein concentration. It has also been used for the quantification of total phenolics. In this method, protein is pretreated with copper(II) in a modified biuret reagent (alkaline copper solution
stabilized with sodium potassium tartrate). Addition of the phenol reagent generates chromogens that give increasing absorbance between 550-750nm. Normally, absorbance at the peak (750nm) or shoulder (660nm) are used to quantitate protein concentrations between 1-100 mg/ml while absorbance at 550nm is used to quantitate higher protein concentrations.
In the absence of copper, color intensity is determined primarily by the tyrosine and tryptophan content of the protein, and to a lesser extent by cysteine and histidine. Copper(II) has no effect on color formation by tyrosine, tryptophan, or histidine, but reduces color formation due to cysteine.
Many modifications of the original assay procedure have been published, including methods for enhancing the color development, for determining the content of insoluble proteins, and for automating the procedure. Compounds including many buffers, chelating agents, detergents, and cyclic organic compounds can interfere with the Lowry protein assay.
Folin & Ciocalteu′s phenol reagent can also be used as a spray reagent in chromatographic procedures.

Application

Folin & Ciocalteu′s phenol reagent has been used for the estimation of total phenolic content in samples.

Other Notes

Folin & Ciocalteu′s phenol reagent does not contain phenol. Rather, the reagent will react with phenols and non-phenolic reducing substances to form chromogens that can be detected spectrophotometrically.

Linkage

This product is also available as part of a kit.

Pictograms

Corrosion
GHS05

Signal Word

Danger

Hazard Statements

H290 - H314

Hazard Classifications

Eye Dam. 1 - Met. Corr. 1 - Skin Corr. 1

Storage Class Code

8B - Non-combustible, corrosive hazardous materials

WGK

WGK 2

Flash Point(F)

Not applicable

Flash Point(C)

Not applicable

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Certificates of Analysis (COA)

Lot/Batch Number
BCCH0732
BCCG2765
SHBL2943
BCCD8944
BCCC7658

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Estimation of total phenolic content and other oxidation substrates in plant tissues using Folin-Ciocalteu reagent.
Ainsworth EA and Gillespie KM
Nature Protocols, 2, 875-875 (2007)
David L Jones et al.
PloS one, 9(3), e90882-e90882 (2014-03-19)
Monitoring the properties of dissolved organic carbon (DOC) in soil water is frequently used to evaluate changes in soil quality and to explain shifts in freshwater ecosystem functioning. Using >700 individual soils (0-15 cm) collected from a 209,331 km(2) area
Han-Shin Kim et al.
Scientific reports, 6, 25318-25318 (2016-05-05)
Biofilm formation on biotic or abiotic surfaces has unwanted consequences in medical, clinical, and industrial settings. Treatments with antibiotics or biocides are often ineffective in eradicating biofilms. Promising alternatives to conventional agents are biofilm-inhibiting compounds regulating biofilm development without toxicity
Nutritional evaluation of some subtropical red and green seaweeds Part II. In vitro protein digestibility and amino acid profiles of protein concentrates.
Wong KH and Cheung PCK
Food Chemistry, 72, 11-17 (2001)
Lowry's method of protein estimation: some more insights.
S Sengupta et al.
The Journal of pharmacy and pharmacology, 45(1), 80-80 (1993-01-01)
View All Related Papers

Articles

Enzymatic Assay of Proteinase K with Hemoglobin Substrate

Proteinase K (EC 3.4.21.64) activity can be measured spectrophotometrically using hemoglobin as the substrate. Proteinase K hydrolyzes hemoglobin denatured with urea, and liberates Folin-postive amino acids and peptides. One unit will hydrolyze hemoglobin to produce color equivalent to 1.0 μmol of tyrosine per minute at pH 7.5 at 37 °C (color by Folin & Ciocalteu's Phenol Reagent).

Enzymatic Assay of Proteinase K with Hemoglobin Substrate

Proteinase K (EC 3.4.21.64) activity can be measured spectrophotometrically using hemoglobin as the substrate. Proteinase K hydrolyzes hemoglobin denatured with urea, and liberates Folin-postive amino acids and peptides. One unit will hydrolyze hemoglobin to produce color equivalent to 1.0 μmol of tyrosine per minute at pH 7.5 at 37 °C (color by Folin & Ciocalteu's Phenol Reagent).

Protocols

Protein Determination Modified Lowry Method

To standardize a procedure for the determination of protein by modified Lowry.

Enzymatic Assay of Proteinase K (EC 3.4.21.64)

Proteinase K (EC 3.4.21.64) activity can be measured spectrophotometrically using hemoglobin as the substrate. Proteinase K hydrolyzes hemoglobin denatured with urea, and liberates Folin-postive amino acids and peptides. One unit will hydrolyze hemoglobin to produce color equivalent to 1.0 μmol of tyrosine per minute at pH 7.5 at 37 °C (color by Folin & Ciocalteu's Phenol Reagent).

Enzymatic Assay of Protease Using Casein As a Substrate

To standardize a procedure for the enzymatic assay of Protease using Casein as a substrate.

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