Ion suppression chromatography is a technique for the separation of ionizable solutes which functions by suppressing the ionization of these solutes, thus increasing their retention on nonpolar stationary phases. In the separation of carboxylic acids, an acidic buffer is added to the mobile phase to suppress the ionization of the solutes, which are then separated on nonpolar polymeric or silica-based (usually C18) stationary phases.

This method is only applicable to those acids for which the ionization can be suppressed using buffers having pH values in the range 3-8, since the C18 stationary phases are unstable outside this pH range. However, these restrictions do not apply to the use of polymeric stationary phases, which can be used for the separation of a wider variety of solutes. The mobile phase is usually an acidic buffer of the appropriate pH. Commonly used buffers include phosphoric acid, sodium or potassium phosphate, sodium hydrogen sulfate, acetic acid and citric acid. Organic modifiers such as methanol or acetonitrile can also be added to the mobile phase to improve the separation.

Solar Panel Basics

Solar Panel Basics

Global warming is a huge problem which will significantly affect every country in the world. Many people all over the world are trying to do whatever they can to help combat the effects of global warming. One of the ways that people can fight global warming is to reduce their dependence on non-renewable energy sources like oil and petroleum based products.

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