HPLC analysis method for acetonitrile
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Everyone* * , where can I find the analysis method of acetonitrile as the mobile phase in liquid chromatography? Both domestic and foreign. grateful. urgent need. This post was last edited by lifanwang on 2009-2-19 17:06 ]
Acetonitrile is HPLCd mobile phase. The purity of acetonitrile cannot be accurately analyzed by HPLC. To analyze the purity of acetonitrile, gas chromatography is required, using an FID detector. The vaporization chamber temperature is 200 degrees Celsius, the column temperature is 60-70 degrees Celsius, and the detector temperature is 200 degrees Celsius. Polyethylene glycol 20M, 0.25X30 column can be used.
Gas chromatography can only analyze organic impurities in acetonitrile. What I am asking is about acetonitrile used in liquid chromatography. Its detectors (UVD, RID, ECD, FD, etc.) should be considered. Now that we need to detect these indicators, where are the standards?
1. I understand that you mean to detect impurities in acetonitrile, use other solvents as mobile phases, and use acetonitrile as the sample for detection. 2. Detect inorganic residues through volatile residues. 3. Use gas chromatography to detect the purity of acetonitrile. The suggestions on the second floor are very good.
If you use acetonitrile as the mobile phase, you should first consider using a UV detector, because the upper limit of the absorption wavelength of acetonitrile is lower, which is 190NM. If you use a differential detector, it is best to use methanol as the mobile phase, because methanol has a lower refractive index than acetonitrile.
I didn't make it clear. My company wants to produce HPLC-grade acetonitrile products (previously industrial-grade acetonitrile) for sale to others, not for our own use. Now I want to find some indicators, standards and corresponding analysis methods. For example, if a user uses acetonitrile as the mobile phase and uses a UVD detector, what are the requirements for the acetonitrile used?
Chinese name: Molecular formula of chromatographically pure acetonitrile: CH3CN level: Premium grade product GC purity ≥99.9% Evaporation residue ≤1mg/l Density (20℃) 0.781- 0.785 (20℃) Refractive index (20℃/D) 1.3440 Moisture ≤0.02% Acidity ≤ 0.0005mmol/g UV transmittance 200nm ≥80% HPLC absorbance 210nm Absorption impurity peak height ≤5mAU Note: The conditions for measuring HPLC absorbance were Venusil-C18 column (4.6 * 50mm, 5ul), the column temperature is 40°C, the flow rate is 3ml/min, the mobile phase system is acetonitrile and water, the acetonitrile gradient increases from 10% to 80% within 6 minutes, and the injection volume is 20ul (neat). 210nm absorption impurity peak height ≤ 5mau 220nm total absorption impurity peak height ≤ 80mau Maximum absorbance value (1cm quartz cuvette water as comparison) 190nm 1.000 200nm 0.050 210nm 0.040 220nm 0.030 230nm 0.010 240nm 0.005 250nm 0.005 Comply with ACS/HPLC solvent standards