What are the advantages of nmr in drug identification and analysis?

NMR has the following advantages in drug identification and analysis:

① The sample preparation method is simple: NMR sample pretreatment is less and easy for quality control, so the sample preparation cost is low and the risk of sample pollution and loss is small;

② Synchronization of identification and detection: in some routine drug analysis and detection process, the identification and quantitative detection of substances are two separate links, while the NMR experiment can provide material structure and content information at the same time, and the preparation of a sample (or even an experiment) can complete the identification and content determination of substances in the sample, so the NMR technology is an efficient and rapid detection Means;

③ Universality of organic compounds: NMR experiment is a non biased test method, which can identify and analyze multiple components in the mixture at the same time, and provides a relatively loose space for the selection of reference materials in quantitative analysis;

④ Strong isomer analysis ability: the unique recognition ability of NMR to isomers is incomparable to many testing technologies (such as chromatography and mass spectrometry).

Explanation:

http://www.creative-biostructure.com/nmr-services_28.htm

looks like the answer is     c     to me!