Design and performance of a high pressure insert for use in a standard magic angle spinning NMR probe

In this paper we describe the construction and performance of high pressure magic angle inserts made from the polymer PEEK. The inserts were designed to fit inside standard commercial 7 mm magic angle spinning rotors and spin at the maximum frequency of the probe. The sample volume of the inserts was 100 microL. A gas loading chamber that operates at room temperature is described. The performance of the inserts is discussed for a number of gases in terms of resolution as a function of spinning speed and leakage of the gas due to permeation through the polymer. Finally, some preliminary results are shown in relation to complex food materials.