HPLC purification testing services

HPLC ( Performance Liquid Chromatography, HPLC) is also called the " pressure Liquid Chromatography ", " Performance Liquid Chromatography", " degree of separation Performance Liquid Chromatography ", "modern column Chromatography”, etc. performance liquid chromatography is an important branch of chromatography, using a liquid as mobile phase, using pressure infusion system, pump mobile phase the single solvents with different polarity or different proportion of mixed solvent and buffer solution into a stationary phase chromatographic column, each component is separated in the column, enter the detector for testing, so as to analysis the sample. This method has become important separation analysis technology in the chemical, medicine, industry, agriculture, commodity inspection and legal inspection, and other disciplines.

performance liquid chromatography (HPLC) method has the characteristics as follows.

A pressure: the mobile phase for liquid, the resistance is bigger flowing through the chromatographic column, in order to through the chromatographic column rapidly, must be to carry liquid with pressure.
B speed: fast analysis speed, fast liquid flow rate, faster than classical liquid chromatography, usually a sample is analyzed in 15 ~ 30 minutes, and even some sample can be completed in 5 minutes, generally less than 1 hour.
C efficiency: separation efficiency. Can choose stationary phase and mobile phase in order to achieve the separation effect, the separation efficiency many times er than industrial distillation and the gas phase chromatography.
D sensitivity: ultraviolet detector can reach 0.01 ng, Injection Volume in mu L orders of magnitude.
E Wide scope of application: more than seventy percent of organic compounds can be analysisedused performance liquid chromatography (HPLC), especially separation and analysis of the boiling point, macromolecular compounds, strong polarity, poor thermal stability chemical compound, show the advantage.
And performance liquid chromatography (HPLC) has many advantages, such as chromatography column can be used repeatedly, sample is not destroyed, easy recycling, ect., but also has shortcomings, compared with gas chromatography strengths and complement each other. The disadvantage of performance liquid chromatography (HPLC) is a "column outside effect". In between injector and detector, besides the pillars of any dead space (injector, column joints, connecting pipe and testing pool, etc.), if a change in the flow pattern of mobile phase, any of the separated material diffusion and the chromatographic peak of retention will be resulted in significantly widened, column efficiency iwill be lower. performance liquid chromatography (HPLC) detector sensitivity is much less than gas chromatography.

Chromatographic characteristics

• pressure can reach 150 ~ 300 kg/cm2. Chromatographic column step-down per meter is more than 75 kg/cm2.
• velocity is 0.1 ~ 10.0 mL/min.
• Effective, plate numbercan be up to 5000 / m. In a column components separated at the same time up to 100 kinds.
• sensitivity, ultraviolet detector sensitivity can reach 0.01 ng. At the same time consuming less sample.
• HPLC has the following advantages compared with classical liquid chromatography.
• Usually the speed of analysis a sample is in 15 ~ 30 min, even some samples can be completed within 5 min.
• resolution, HPLC can choose the stationary phase and mobile phase in order to achieve the separation effect.
• sensitivity, ultraviolet detector can reach 0.01 ng, fluorescent and electrochemical detector can reach 0.1 pg.
• Chromatographic column can be used repeatedly, different compounds can be separated with a chromatographic column.
• Less sample, easy to recycle, the sample after chromatographic column is not damaged, can collect a single component or do preparation.