NUCLEAR MAGNETIC RESONANCE METHOD FOR QUANTITATIVE AND QUALITATIVE MEASUREMENT OF NATURAL PRODUCTS

摘要

Provided herein are various methods and systems for analyzing natural products by quantitative proton nuclear magnetic resonance (qHNMR). A method is provided for quantitative and qualitative determination of a natural product by ¹HNMR and decoupling ¹³C nuclei from the protons in the sample containing the natural product. The resultant spectrum wherein the decoupling provides a cleaner spectrum is used to provide both structural and quantitative information about species within the sample. In an aspect, the decoupling is provided by globally optimized alternating-phase rectangular pulses (GARP). The methods presented herein are optionally used to detect impurities in a reference material and verify the purity level of a reference material.