4-Hydroxycoumarin CAS 1076-38-6 Purity >99.0% (HPLC)

4 Test method
4.1 Appearance (visual inspection)
4.2 Loss on drying
4.3 Determination of 4-Hydroxycoumarin content
4.3.1 Determination method
The samples were dissolved in mobile phase and determined by high performance liquid chromatography on C18 column by peak area normalization method.
4.3.2 Reagent
a) Acetonitrile: chromatographic pure (imported);
b) Water: Deionized water or secondary distilled water.
4.3.3 Instrument
a) High performance liquid chromatography;
b) UV-adjustable wavelength spectrometer;
c) Analysis column: C18 column;
d) Ultrasonic oscillators.
4.3.4 Chromatographic operating conditions
a) Mobile phase: acetonitrile: water: phosphoric acid = 700:300:1 (V/V/ V);
b) Flow rate: 1.0ml/min;
c) Column temperature: room temperature;
d) Detection wavelength: 254nm
e) Sample size: 20μL
4.3.5 Preparation of test solution
Weigh the sample 20mg (accurate to 0.002g), place it in a 25ml volumetric bottle, dissolve it with mobile phase in 4.2.4 a) to the scale, shake it well in an ultrasonic shaker for later use.
4.3.6 Content determination
Under the conditions of 4.3.4 above, the test solution shall be determined after the instrument is stabilized.
4.3.7 Calculation
The peak area normalization method was used to calculate the results.
4.3.8 Permissible deviation
The deviation of the two measurements is no more than 0.5%, and the calculated average value is taken as the test result.
4.4 Determination of melting point.
5 Inspection Rules
5.1 Each batch of products shall be tested by the quality inspection department according to the items in this standard before leaving the factory.
5.2 Determination of batches
A batch of products produced by a feeding quantity (about 200kg).
5.3 Sampling
Two bags (barrels) are randomly selected from the packaging of each batch of products. After sampling and mixing evenly, they are divided into 50g by the method of four parts, which are divided into two parts, one of which is used for testing and the other is kept for reference.
5.4 Decision
Each batch of products shall be tested according to the requirements set forth in this standard. If any item fails to meet the requirements set forth in this standard, it shall be allowed to retest by double sampling. If there is still one item that fails to meet the requirements set forth in this standard, the batch of products shall be judged unqualified.
5.5 Arbitration
The User has the right to conduct acceptance inspection within 15 days after receiving the goods according to the provisions of this standard. In case of any quality objection, both parties may negotiate to settle it, or entrust the statutory arbitration institution agreed by both parties to conduct arbitration according to the provisions of this standard.
6 Labels and labels
The following marks shall be affixed to the product package:
a) Product name;
b) Standard number;
c) Net weight;
d) Production date or batch number;
e) Name and address of the factory;
f) Shelf life.