HR-$\mu$MAS NMR localized metabolic profiling of $\mu$g samples: a model study

Covadonga Lucas-Torres (1) , Yusuke Nishiyama (2) , Alan Wong (1)

1 LSDRM - Laboratoire Structure et Dynamique par Résonance Magnétique (LCF)
2 JEOL Ltd, 1156 Nakagami, Akishima, Tokyo 196-0022, Japan.

NMR has already proven to be a tremendous spectroscopic tool in metabonomics. However, due to its low detection sensitivity, NMR analyses can be challenging especially for mass-limited samples. To overcome this issue, here we introduce a 'new' reliable methodology for profiling $\mu$g/nL scale samples based on the Magic Angle Spinning (MAS) technique-High-Resolution $\mu$MAS (i.e. 1 mm HR-$\mu$MAS). A model study has been proposed: the localized metabolic profiling (i. e. mapping) of a garlic clove. We have been able to investigate 4 different regions (clove skin, flesh, core and inner epidermis), whereas only 3 regions were distinguished using the standard approach, HR-MAS with larger sample mass ($\sim$10 mg). The use of multivariate statistical analysis allowed an initial separation between the different regions by unsupervised PCA. Based on this PCA, a supervised discriminant analysis OPLS was carried out between the previously separated clusters to find the discriminant metabolites. The fact that these micro-detections have been able to offer such precise and accurate results on a model study, opens the way to new applications on heterogeneous biospecimens (such as tissues and cells), on the determination of NMR-based localized metabolic profiles to get the comprehensive fingerprint of their different anatomical regions.

Domains: Material chemistry

Covadonga Lucas-Torres, Yusuke Nishiyama, Alan Wong. HR-$\mu$MAS NMR localized metabolic profiling of $\mu$g samples: a model study. VIII Ibero-American NMR meeting # 6th Iberian NMR Meeting # 9th GERMN # 4th Portuguese RNRMN Meeting, Jun 2018, Lisbon, Portugal. ⟨cea-02327970⟩