CHROMATOGRAPHIC - 121 Annonces

Samedi 28 septembre 2019

Depending on the packing of the HPLC column. The following column types are available on the market: 1. Silica gel HPLC column: Silica gel is the earliest chromatographic column packing used in liquid chromatography. It has a wide range of applications. However, it can only be used...

Vendredi 27 septembre 2019

Reliable flash columns play a decisive role in a good chromatographic separation method, which ensures complete separation of valuable compounds and specific impurities. Choosing the right flash column is the most critical part of the purification process. There are two aspects should...

Jeudi 26 septembre 2019

- Reversed-Phase Principle - The reversed-phase filler is a kindly of nonpolar filler such as C4, C8, C18 aliphatic chain which is bonded on the silica gel. Nonpolar or hydrophobic compounds are strongly reserved, while polar samples are weakly reserved and go through the flash reversed-phase...

Mardi 24 septembre 2019

Syringe filter is suitable for the filtration of a small number of samples in the laboratory. The adsorbability of syringe filter to samples is weak, which ensures the large number of recovery of small or high-value samples. The outer shell of the filter is made of polypropylene and...

Mardi 24 septembre 2019

Ion Chromatography is one of high-performance liquid chromatography (HPLC) and is a liquid chromatography method for the analysis of anions and cations. In a narrow sense, ion chromatography is a chromatographic method in which a low exchange capacity ion exchange resin is used as...

Vendredi 20 septembre 2019

Syringe filter can be used in the analysis of high performance liquid chromatography and IC. It is an important step in sample pretreatment to filter sample solution. The syringe filter with high quality is produced by using the most advanced detection means and production technology...

Vendredi 20 septembre 2019

Silica matrix HPLC columns are generally compatible, but organic polymer matrix columns may expand or contract in some solvent combinations, which will affect their chromatographic behavior. Wash each solvent system at least 20 volumes. Because some solvent systems are highly viscous...

Vendredi 20 septembre 2019

Solid phase extraction is essentially a liquid chromatographic separation. The main separation mode is the same as that of liquid chromatography. It can be divided into normal phase (the polarity of the adsorbent is greater than the polarity of the eluent), and the reverse phase (the...)

Mercredi 18 septembre 2019

In the analysis of HPLC, the packing size of chromatographic column is small, and it is easy to be blocked by impurity particles. Therefore, samples and solvents need to be pre-filtered to remove particulate pollutants and protect chromatographic columns and instruments. Ion chromatography...

Mercredi 18 septembre 2019

In chromatographic experimental analysis, a device that can quantitatively feed a sample bottle into a chromatographic column is called a sample vial. Sample vials are divided into manual and automatic sample vials. The automatic sample vial is an intelligent and automatic sampling...

Mardi 17 septembre 2019

Adsorption chromatography uses the difference in adsorption capacity of substances in stationary phase adsorption to achieve separation of the mixture. The chromatographic process of adsorption chromatography is the process in which the mobile phase molecules compete with the material...

Jeudi 12 septembre 2019

As an important branch of chromatography, high-performance liquid chromatography (HPLC) has become an important application of separation and analysis technology in the fields of chemistry, medicine, industry, agriculture, commodity inspection, and law inspection. Features of high-performance...

Mardi 10 septembre 2019

According to the separation mechanism of substances, Chromatography can be divided into adsorption chromatography, distribution chromatography, ion exchange chromatography and the like. The operation mode of the adsorption thin layer chromatography refers to that the adsorption capacity...

Mardi 03 septembre 2019

Chemical properties of the chromatographic column could affect the performance of the C18 HPLC column. Performance factors of C18 HPLC columns: bonding type Single tooth bonding can improve the mass transfer rate and accelerate column balance. Double tooth bonding can increase the...

Vendredi 16 août 2019

NH2 HPLC columns refer to the chromatographic columns that use silica gel as matrix carrier to bond amino groups. They are usually used for the analysis of carbohydrate compounds, and the mobile phase is usually methanol, acetonitrile and buffers salt solution. - The cleaning method...

Jeudi 15 août 2019

The similarities FLASH and SPE are all column chromatography separation technology. FLASH is a fast separation mode for preparative chromatography, using optimized pre-packed low and medium pressure columns for chromatographic separation. The separation mechanism, stationary phase...

Mercredi 14 août 2019

Flash column chromatography is an alternative to long column chromatography developed in 1978. This method aims to separate the components from the mixture and thereby purify it. It is built from existing long column chromatography techniques and is time-consuming and often unsatisfactory...

Mercredi 14 août 2019

Physical properties of the chromatographic column could affect the performance of C18 HPLC columns. - Performance factors of C18 HPLC columns: - Silica gel purity Class A silica gel has high residual silica hydroxyl with a negative charge and high metal content on the acidic surface...

Mardi 13 août 2019

Syringe filter is suitable for filtering a small number of samples in the laboratory because of its low adsorbability. The low adsorbability ensures a large amount of recovery of small or high-value samples. The shell of the filter will not pollute the samples. It has stable quality...

Lundi 12 août 2019

Syringe filter is a kind of filter connected to the front of the syringe. When the experimenters deal with the chromatographic samples with syringe filter, they should pay attention to avoiding bringing impurities in the process of filtration. One reason for the appearance of such...

Lundi 12 août 2019

With the continuous development of the sample vials, more and more types and functions of the sample vials appear in laboratory analysis. The capacity of sample vials is bigger and bigger. The sampling speed of the sample vials is faster and faster. The sampling accuracy is higher and higher...

Lundi 12 août 2019

The rapid chromatographic method is a technology widely used in the separation and purification of active target compounds, such as organic compounds, natural products, and biological macromolecules. Rapid chromatographic method has the advantages of easy-operation, low-price, and fast-analysis...

Lundi 12 août 2019

The system of an HPLC column is composed of a liquid, a reservoir, a pump, a sampler, a column, a detector and a recorder. - The packing material of HPLC columns - The packing material has high carbon content, small surface polarity, very low chemical purity and high surface separation...

Vendredi 09 août 2019

Reversed-phase chromatography (RPC) contains any chromatographic method using a non-polar stationary phase. The word “reverse” has a historical background. In the 1970s, most liquid chromatography was performed on unmodified silica or alumina. Their surface chemistry is hydrophilic...

Jeudi 08 août 2019

More than 90% of gas chromatographic problems occur in the inlet, and it is necessary to see which problems may occur in the inlet. Problem No.1: Leak If there is a leak, the pressure on the inlet may not be maintained, and the instrument will alarm. If the problem cannot be solved in time...

Jeudi 08 août 2019

Flash columns adopt high-capacity silica gel for precise filling, which has very excellent separation and purification performance. The specific surface area of high-capacity spherical silica gel is 40% higher than that of ordinary spherical silica gel, and the sample loading is twice...

Jeudi 08 août 2019

Chromatography is a separation and analysis method and the separation is the core. Therefore, HPLC columns are the heart of the chromatographic system. The requirements for the column are high efficiency, good selectivity and fast analysis speed. Generally, the column length of about...

Jeudi 08 août 2019

Most common SPE cartridges are injection syringes made of polyethylene, in which there are two plugs made of polypropylene or fiberglass, with a certain amount of chromatographic adsorbent (filler) between the two plugs. SPE cartridges without sieve plate 1. Avoid “non-specific adsorption” 2...

Mercredi 07 août 2019

Food safety testing is a major issue related to people's livelihood. In recent years, the QuEChERS method has been widely used in the pretreatment of food safety detection samples. In addition, the method has been applied to trace analysis. QuEChERS Application The international application...

Mardi 06 août 2019

In recent years, the application of HPLC in inorganic analysis has developed rapidly, and the use of flash columns has been more and more widely because of a method that can rapidly determine heavy metal elements in environmental water samples. Matters needing the attention of flash columns 1...