Solid phase extraction (SPE) is a sample preparation technology which develops and combines between liquid-solid extraction and column-liquid phase chromatography technology in these years. SPE is mainly used for sample separation, purifying and condensation. Compared with the traditional liquid-liquid extraction, SPE can increase the analyte recovery rate, separate analyte and interfering components efficiently and simplify the sample preparation process. SPE is easy to operate and save time. Let’s know more about the SPE. SPE column Read more…

Gas chromatography Gas chromatography is a easy, fast, efficient, sensitive, modern separation analysis technology which is widely used in environment, medicine, chemical industrial department, and it’s also an indispensable way to test Pesticide Residues. Gas chromatography has fast analysis, high efficient separation, high sensitivity, high selectivity and other advantages. While during the analysis, Gas chromatograph may face various failures because of complex sample matrix, operator failures, device failures and etc. Therefore, it’s very important to Read more…

There are several different names in China and other countries for Reference Materials and also different names with different systems. Here we use Reference Materials (RM). There are 2 measuring standard substances in ISO system which are Reference Materials (RM) and Certified Reference Materials (CRM). According to ISO Guide 30, Reference Materials/Standard Materials are uniform and stable substances with one or more than one specific properties, and they are also materials or substances which are Read more…

During the liquid phase chromatograph experiment, we always face some issues, like the retention time shift. It’s a headache problem, and there are so many factors causing the peak retention time shift, like if the mobile phase fully balanced; if the mobile phase and stationary phase are well selected; if solvent effect is existing. But what if we exclude those influences, there are still problems, what can we do? Let’s see the case: Citric acid Read more…

When you operate ion chromatograph or mass spectrometry detection, you find some impurity peak issues, maybe because it’s caused by the test matter or the sensitivity. It’s quietly probably cased by the sample vial. In this situation, we need use some specials to solve this issue. The ordinary chromatography is used to detect the organic, but we may detect some sodium ions or calcium ions in the ion chromatograph. These kind of ions exist in Read more…

Phase Collapse It always can be heard in the hydrophobic interaction chromatograph/reverse chromatography, comes as no reservation to the matter, peak time ahead making no reservation between peaks. Case: Chromatography column: Ultimate® XB-CB 21.2×250mm, 10μmFlowing phase: approximate pure water The 1st day → the normal activation feeding chromatogram No feeding in the night, because of no additive like acid and alkali in the flowing phase, so shutting down after cleaning auto-feeder. The 2nd day → Read more…

Super inertia/Low running off/High efficiency/Long life During the gas chromatography, the chromatographic column may be called the heart of the gas chromatograph and it plays the important role for analyzing the group to be tested. Today, in order to choose chromatographic columns well, let’s learn about relevant specification parameters of the gas chromatography column. There are 2 types of GC which are the packed column and the capillary column, the filler which is inside of Read more…

MCC Summary Mixed-mode chromatography (MMC) is a high efficient chromatography which can optimize the design of the functional ligand structure, mix 2 or more than 2 interaction modes, enhance the target protein’s affinity and selectivity. Compared with traditional IEC and HIC, this new mode MMC has so many advantages like high-load, high selectivity, high efficiency and etc. MMC’s characteristic There are many interaction modes between MCC ligand and the target protein, such as the hydrophobic Read more…

The difference between the protein purification lab and general biotech or molecular biology lab is necessary consumables and instrument in protein purification. The centrifuge is the general instrument in the lab. And the main instrument in protein purification lab is High-speed refrigerated centrifuge which can reach to 2000r/min speed, and the practicability of it is directly relating to the quantity of kinds of matched rotor, centrifuge tube and centrifuge barrel. Rotors match to all kinds Read more…

As the protein chemistry and molecular biology grow rapidly, the development and application of protein drugs for the treatment of various diseases has become a hot spot in biomedical industry. Polypeptides and protein drugs have mild adverse effects and strong activity while addressing both the symptoms and root cause. When we purify proteins, keeping the protein from inactivation and minimizing the loss of protein activity caused by the purification process are of primary significance. Hence, the following factors should be Read more…