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INADEQUATE measurement using SuperCOOL probe

It is often difficult to unambiguously determine structures of molecules, which have many non-protonated carbon atoms. Because such compounds contain quaternary carbons, lack protons and bonding to quaternary carbons each other, HMBC (Heteronuclear Multiple Bond Correlation) experiment cannot provide long-range 1H-13C connectivity. Therefore, INADEQUATE (Incredible Natural Abundance DoublE QUAntum Transfer Experiment), which is 13C-13C correlation experiment at natural 13C abundance, represents a powerful tool for proton-diluted compounds.

A 1H Solid State NMR Application for Pharmaceutical Development by using Ultra Fast MAS: Drug-Polymer Intermolecular Interaction on Solid Dispersions_NM190003E

The low oral bioavailability of a drug due to its poor aqueous solubility is a major challenge for pharmaceutical development. Solid dispersion (SD), where the amorphous drug is dispersed into the polymer matrix, is one of the useful approaches to improve the aqueous solubility. However, thermodynamically unstable nature of an amorphous drug increases its susceptibility to recrystallize upon storage, which, in turn, reduces its solubility and dissolution. Therefore, design of thermodynamically stable SD is required.

Overtone solid-state NMR spectroscopy on Nitrogen-14_NM180002E

15N NMR is widely used because of the importance of nitrogen in chemistry, materials, biology, environment, etc. However, very low abundance of 15N (<0.4%) results in poor sensitivity and thus makes observation time-consuming. On the other hand, the rest of nitrogen atoms are also NMR sensitive nucleus of 14N. Despite the high abundance of 14N (>99%), it's application is rather limited due to the huge quadrupolar interactions and its spin quantum number I = 1.

Analytical Instruments Documents

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Corona - Glow Discharge (DART Ion Source)

February 22, 2020
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