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Application of high-field NMR spectroscopy for characterization and quantitation of submilligram quantities of isolated natural products.

ABSTRACT: We have investigated and compared a number of sample conditions on different NMR platforms in the search of maximum SNR and optimal experiment time efficiency for structure elucidation and quantitation of natural products. Using restricted volume 3?mm Shigemi microcell assembly in conjunction with a 900?MHz NMR spectrometer equipped with a 5?mm carbon-sensitive inverse cryoprobe, it was possible to achieve a substantial increase in SNR (46-fold) as compared with a conventional room temperature 400?MHz instrument. Switching from standard 5?mm NMR tube to 3?mm Shigemi microcell assembly typically improved SNR by threefold on either 600 or 900?MHz cryoplatform. A quantitation method that relies on a calibrated residual protonated NMR solvent signal as internal standard was developed using the same hardware setup and restricted sample volume tubes. Linearity of the method spans over 3 orders of magnitude, from low microgram to milligram quantities. We successfully applied this method to quantify a low micrgram sample of paclitaxel, verified by a UV/VIS quantitation measurement.

SUBMITTER: Krunic A

PROVIDER: S-EPMC4752180 | biostudies-other | 2015 Dec

REPOSITORIES: biostudies-other

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Application of high-field NMR spectroscopy for characterization and quantitation of submilligram quantities of isolated natural products.

Krunić Aleksej A Orjala Jimmy J

Magnetic resonance in chemistry : MRC 20150820 12

We have investigated and compared a number of sample conditions on different NMR platforms in the search of maximum SNR and optimal experiment time efficiency for structure elucidation and quantitation of natural products. Using restricted volume 3 mm Shigemi microcell assembly in conjunction with a 900 MHz NMR spectrometer equipped with a 5 mm carbon-sensitive inverse cryoprobe, it was possible to achieve a substantial increase in SNR (46-fold) as compared with a conventional room temperature 4 ...[more]

PMID: 26289113

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Dataset Information

Application of high-field NMR spectroscopy for characterization and quantitation of submilligram quantities of isolated natural products.

Publications

Application of high-field NMR spectroscopy for characterization and quantitation of submilligram quantities of isolated natural products.

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