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Sample filtration is one of the important processes in pre-treatment, which aims to remove impurities and obtain filtrate to improve the accuracy of experiments and reduce the harm caused by solution particles to experimental equipment. As the most commonly used consumable for sample filtration in the laboratory, how to choose a suitable needle filter is crucial. Choosing the wrong needle filter can lead to prolonged experiment time, the need to repeat the process, and wasted Read more…
Column activation is necessary if the chromatographic column has dried out due to various reasons, and it needs to be wetted with the corresponding storage solvent before use to avoid potential damages. Without activation, normal peaks cannot be obtained, leading to incomplete detection or even damage to the chromatographic column. Therefore, if the filling of the column has dried out, activation is required. What are the situations that may cause the filling to dry out Read more…
Last time, the author briefly introduced the differences between high-performance liquid chromatography (HPLC) and ultra-high-performance liquid chromatography (UHPLC). It is believed that everyone now has a more specific understanding of the two. With the development of small particle chromatographic columns, more and more industry professionals expect to use sub-2μm particle size chromatographic columns in UHPLC to broaden selectivity, improve work efficiency, reduce energy consumption, and reduce pollution. Today, we will guide everyone on how to Read more…
Those who have experience with experiments know that High-Performance Liquid Chromatography (HPLC) and Ultra Performance Liquid Chromatography (UPLC) are commonly used component separation techniques in the laboratory. Given their common functions, many may find it difficult to distinguish between the two. In the following paragraphs, the writer will provide a brief explanation of the dissimilarities between HPLC and UPLC to aid readers in comprehending these two methods. Definition of High-Performance Liquid ChromatographyHigh-Performance Liquid Chromatography (HPLC), Read more…
Column Xtimate® SEC-120（7.8×300mm，5μm) Mobile Phase 0.1 M sodium nitrate solution Detection wavelength Differential detector temperature: 30℃ Temperature 30℃ Flow Rate 0.6 mL/min Injection 20 μL
Column Welch Xtimate® C18（4.6×250mm，3μm) Mobile Phase Detection wavelength 361nm Temperature 35℃ Flow Rate 1.1ml/min Injection 20μL
Column Xtimate® C18（4.6×150mm，5μm) Mobile Phase Mobile phase A: 0.01 mol/L Potassium Dihydrogen Phosphate Solution (pH 6.0 adjusted with 2 mol/L Sodium Hydroxide Solution). Mobile phase B: 0.01mol/L potassium dihydrogen phosphate solution (adjusted with 2mol/L sodium hydroxide solution section pH6.0)/acetonitrile=20/80 Detection 230nm Temperature 35℃ Flow Rate 1.0ml/min Injection Volume 20 μL
Column Ultisil® SEC-120(7.8×300 mm,5 μm) Mobile Phase Ultrapure water Detection Evaporative light scattering detector, drift tube temperature 100°C, carrier gas3.5bar Temperature 35℃ Flow Rate 1.0ml/min Injection Volume 10 μL
Baseline drift can be a real headache for researchers and analysts working with data. It refers to the gradual and undesirable changes in the baseline signal of a measurement, which can obscure or distort the true variations in the data over time. Common causes of baseline drift include changes in temperature, pressure, humidity, or instrument performance, as well as sample evaporation or degradation. Here we have listed some common problems of baseline drift for you. Read more…
Have you ever encountered issues such as fronting, peak broadening, splitting, etc. during liquid phase system analysis? Why does reducing the injection amount of the same sample sometimes result in a better-looking chromatographic peak? In daily analysis work, we usually focus more on the selection of mobile phase and instrument methods, and neglect the importance of sample injection solvents. If the solvent selection is improper, it will lead to “solvent effects”, causing errors in qualitative Read more…