Sample preparation process for HPLC analysis

The process of preparing the sample to be tested in high performance liquid chromatograph analysis. For this purpose, samples must be prepared efficiently. Sample preparation for HPLC analysis includes pretreatment, extraction, purification, and concentration.

1. Pretreatment:

1. Solid sample: low water content, crushed and sieved. The water content is high, take the used part and dry it, crush it and sieve it.

2. Liquid samples: Stir to mix evenly.

3. Special samples: special treatment according to experimental requirements.

2. Extraction:

1. Leaching method (solid-liquid extraction method): soak the sample in a solvent to extract some components from the solid sample .

2. Extraction method (liquid-liquid extraction method): separation is achieved using the difference of cdistribution coefficient of the extracted component in two immiscible solvents.

3. Purification:

1. Extraction of methamphetamineod: suitable for liquid samples, small amount and multiple times.

2. Chemical method: Changing the solubility of impurities or analytes through chemical reactions to separate them from the original system.

3. Chromatography: Using the different physical and chemical properties of each component in the mixture, the speed of movement of each component on the medium is different, and the components are separated.

4. Concentration:

1. Concentration at atmospheric pressure: By raising the temperature, the solvent is converted from a liquid state to a gaseous state and then drawn in, so as to reach the goal of concentration. Suitable for samples with relatively low volatility and boiling point.

2. Concentration under reduced pressure: thanks to the vacuum,negative pressure is generated in the vessel and the boiling point of the sample is lowered without changing the chemical properties of the sample, so some chemical properties are unstable at high temperature or the boiling point is high. The solvent is converted from liquid to gas at low temperature, then pumped, so as to achieve the concentration target.

3. Lyophilization: During freezing, vacuum and decompress at the same time to sublimate the solvent. Suitable for biologically active samples.

4. Concentration with nitrogen blowing instrument: use nitrogen to purge the heated sample, so that the sample can be quickly concentrated to achieve the effect of separation and rapid cleansing. It is suitable for batch processing of samples such as pesticide residue detection and pharmaceutical industry.

I hope you find the above content helpful.has useful. If in doubt, please call the manufacturer for consultation.

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