Triethyl Citrate柠檬酸三乙酯.pdf

IECC V
Monographs /di-tryptophan/489
Nonvolatile Residue (Caution: Carry out this procedure in Acidity(as citric acid)Dissolve 32 g o[ sample, accurately
a fume hood )Evaporate 69 ML(about 100 )of sample to weighed, in 30 ML of alcohol neutralized to bromothymol
dryness in a tared dish on a steam bath, dry the residue at blue, and titrate with 0.1 N sodium hydroxide. Not more than
105 for 30 min, cool, and weigh
1.0 ML is required
Specific Gravity Determine by any reliable method(ee Lead Determine as directed in the Lame Atomic option
Genera Provisio
Spectrophotometric Method under Lead Limi fest, Appendix
Water Determine as directed under Water Delerminalion
1B, using a 10-g sample
Appendix TB
Refractive Index Determine as directed under Refractive
Index, Appendix TIB, using an Abbe or other refractometer
Packaging and Storage Store in tight containers
of equal or greater accuracy
Specific Gravity Determine by any reliable method (see
Genera/ Provisions
Water Determine as directed under Water Determination
Appendix IB
Triethyl Citrate
Ethyl Citrate
Packaging and Storage Store in well-closed containers
CH2CO0C2H5
LHO
COOC2H5
CH2 COOC>H
DI.-tryptophan
Dl-q-amino-3-indolepropionic Acid
C1H200
Formula wt 276. 29
lNS:]519
AS:177-93-0
OH
N
DESCRIPTION
H
Triethyl Citrate occurs as a practically colorless, oily liquid
It is slightly soluble in water, but is miscible with alcohol C,HN,O
Formula wl 204.22
and with ether
CAS:154-12-6
Function Solvent
REQUIREMENTS
IDESCRIPNON
ssay Not less than 99. 0% and not more than 100.5% of Dl-tryptophan occurs as white crystals or as a crystalline
C12 H2007, calculated on the anhydrous basis
powder. It is soluble in water and in dilute acids and alkalies
Acidity(as citric acid )Not more than 0.02%
It is sparingly soluble in alcohol. It is optically inactive
Lead Nol more than 2 mg/kg
Refractive Index Belween 1439 and 1.443 al 25o. or b
Function Nutrient
tween 1.440 and 1444 at 200
Specific Gravity Between 1.135 and 1.139 at 25
REQUIREMENTS
Water Not more than 0.25%
Identification The infrared absorption spectrum o! the sam-
TESTS
le exhibits relative maxima at the same wavelengths as those
of a typical spectrum as shown in the section on Infrared
Assay Transfer aboul 1.5 g of sample, accurately weighed, Spectra, using the same test conditions as specified therein
into a 500-ML flask equipped with a standard-laper ground Assay Not less than.5% and not more than 101.5% of
joint, and add 25 ML of isopropyl alcohol and 25 ml of water. CU1H N,>, calculated on the dried basis
ipet 50 ML of 0.5 N sodium hydroxide into the mixture, Lead Not more than 5 m/k
add a few boiling chips, and attach a suitable water-cooled Loss on Drying Not more than 0.3%
condenser. Reflux for 1.5 h. then cool. wash down the con-residue on Ionition Not more than 0.1%
denser with aboul 20 ml of water, add 5 drops of phenolphtha
lein TS. and titrate the excess alkali with 0.5 W sulfuric acid
Perform a blank determination( see Genera/ Provisions), and
TESTS
make any necessary correction. Each milliliter of 0.5 N sodium Assay Dissolve about 300 mg of sample, previously dried
hydroxide