Top 10 High Performance Liquid Chromatography (HPLC) Analysis Services
Its high quality and resolution make HPLC one of the most popular chromatographic technique, and you have probably already needed it.
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It is an analytical method used to separate, identify and quantify chemical compounds such as carbohydrates, amino acids, proteins or organic acids. Like liquid chromatography, the sample is pushed through a column filled with very small particles to separate the different components. What distinguishes HPLC from traditional liquid chromatography is the significantly higher pressure (from 50 to 350 bar) under which the liquid passes through the column. This, with the smaller size of the particles in the column, gives HPLC the ability to separate and identify the different compounds of a sample present in trace concentrations in reducing time, hence its qualification of “High Performance”. It is a powerful technique which allows both qualitative and quantitative analysis.
Different types of HPLC exist according to what you need to analyze.
Reverse Phase Chromatography (RPC)
Reverse Phase Chromatography (RPC) utilizes hydrophobicity to separate proteins peptides and nucleic acids. Because of its high resolution, the method is widely used for purity check analysis. But because many proteins are denatured by organic solvents used in this method, it is not recommended for preparative protein purification.
Hydrophobic Interaction Chromatography (HIC)
Hydrophobic Interaction Chromatography (HIC) also separates molecules according to their hydrophobicity. Unlike RPC, HIC is a useful separation technique for purifying proteins because it utilizes less denaturing conditions helping to preserve the biological activity of the proteins.
Ion Exchange Chromatography (IEC)
Ion Exchange Chromatography (IEC) involves the separations of charged molecules which binds to oppositely charged molecules in the column. With this method, it is possible to separate molecules with even small differences in charge by choosing the optimal ion exchanger and separation conditions.
Affinity Chromatography (AC)
Affinity Chromatography (AC) utilizes the reversible interaction between a target protein and a specific ligand to separate molecules. Two types of interactions can be used: specific interactions with antibodies for example or nonspecific interaction like a protein binding to metal ions. Because of its high selectivity, separations by AC can be done with high purity in a single step. AC can also be utilized to remove specific contaminants from the sample.
Size Exclusion Chromatography (SEC)
Size Exclusion Chromatography (SEC) is the simplest chromatography method that separates molecules according to their size and thus is used to separate large molecules. SEC is very flexible and can be used with aqueous solutions ( gel filtration chromatography) or organic solutions ( gel permeation chromatography) and allows you to choose the optimal conditions for your sample. Another advantage is that, in certain experimental conditions, it is possible to determine approximate molecular weight. It is usually applied to separate macromolecules such as proteins, polysaccharides or industrial polymers.
Multimodal or mixed-mode Chromatography (MMC)
Multimodal or mixed-mode Chromatography (MMC), is a chromatographic method which combines two or more types of chromatography to complete the components separation. The combination of several separations can give MMC a higher selectivity.
It often takes time to find the CRO which corresponds to your needs. Here you can find a selection of services which can be useful for you.