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Merck
CN

791725

Citric acid

anhydrous grade, ACS reagent grade, ≥99.5%, Redi-Dri™, free-flowing, crystals

Synonym(s):

2-Hydroxy-propane-1,2,3-tricarboxylic acid

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About This Item

Linear Formula:
HOC(COOH)(CH2COOH)2
CAS Number:
77-92-9
Molecular Weight:
192.12
NACRES:
NA.21
PubChem Substance ID:
329768287
UNSPSC Code:
12352100
EC Number:
201-069-1
MDL number:
MFCD00011669
Beilstein/REAXYS Number:
782061

Key Documents

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Product Name

Citric acid, anhydrous, free-flowing, Redi-Dri™, ACS reagent, ≥99.5%

InChI key

KRKNYBCHXYNGOX-UHFFFAOYSA-N

InChI

1S/C6H8O7/c7-3(8)1-6(13,5(11)12)2-4(9)10/h13H,1-2H2,(H,7,8)(H,9,10)(H,11,12)

SMILES string

OC(=O)CC(O)(CC(O)=O)C(O)=O

grade

ACS reagent
anhydrous

product line

Redi-Dri™

assay

≥99.5%

form

crystals

quality

free-flowing

expl. lim.

8 %, 65 °F

impurities

Substances carbonizable by hot sulfuric acid, passes test

ign. residue

≤0.02%

pKa 

(1) 3.13, (2) 4.76, (3) 6.4

mp

153-159 °C (lit.)

anion traces

chloride (Cl-): ≤0.001%
oxalate (C2O42-): passes test (limit about 0.003%)
phosphate (PO43-): ≤0.001%
sulfate (SO42-): ≤0.002%

cation traces

Fe: ≤3 ppm
Pb: ≤2 ppm

functional group

carboxylic acid
hydroxyl

Quality Level

200

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Application

Citric acidhas been used as a component of citrate buffer and Fe-free sauton′s medium. It has been used in hybridization chain reaction buffer for preequilibration of coverslips for testes sections.

General description

Citric acid also called 2-hydroxy-propane-1,2,3-tricarboxylic acid, is a component of the tricarboxylic acid cycle in all organisms. Industrial production of citric acid use fungal, yeast and citrus fruit as the major source. Aspergillus niger is majorly used for citric acid production by fermentation Manganese inhibits fermentative production of citric acid Oral supplementation of citric acid promotes tricarboxylic acid cycle and oxidative phosphorylation in mitochondria, attenuating physical fatigue.

Legal Information

Redi-Dri™ is a trademark of Sigma-Aldrich Co. LLC
Redi-Dri is a trademark of Sigma-Aldrich Co. LLC

pictograms

Exclamation mark
GHS07

signalword

Warning

hcodes

H319,H335

Hazard Classifications

Eye Irrit. 2 - STOT SE 3

target_organs

Respiratory system

Storage Class

11 - Combustible Solids

wgk

WGK 1

flash_point_f

Not applicable

flash_point_c

Not applicable

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Certificates of Analysis (COA)

Lot/Batch Number
0000502517
0000449541
0000449541
0000443308
0000443308

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Biochemical studies of citric acid production and accumulation by Aspergillus niger mutants
Gupta S and Sharma CB
World Journal of Microbiology & Biotechnology, 18(5), 379-383 (2002)
A comprehensive roadmap of murine spermatogenesis defined by single-cell RNA-seq
Green CD, et al.
Developmental Cell, 46(5), 651-667 (2018)
Two promoters in the esx-3 gene cluster of Mycobacterium smegmatis respond inversely to different iron concentrations in vitro
Fang Z, et al.
BMC Research Notes, 10(1), 426-426 (2017)
Biotechnological production of citric acid
Max B, et al.
Brazilian Journal of Microbiology, 41(4), 862-875 (2010)
Effects of citric acid and L-carnitine on physical fatigue
Sugino T, et al.
Journal of Clinical Biochemistry and Nutrition, 41(3), 224-230 (2007)
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