Preparation of sample for NMR analysis and integration - Essay Example

PREPARATION OF SAMPLE FOR NMR ANALYSIS AND INTEGRATION Submitted Summary Nuclear magnetic resonance (NMR) spectrometry is a powerful tool used to recognize the novel compounds chemical structures. To acquire high quality spectra for the elucidation of structure, the NMR method needs relatively large amounts of pure compound, which often needs substantial purification from the extracts or the other compound mixtures. The requirement for large amounts of pure compound is because of the relatively low sensitivity of NMR and the lack of a compound separation system in analysis of NMR.

The Purpose of this paper will be to discuss the sample preparation for NMR integration and analysis. Unlike the other spectroscopy types, the sample quality in NMR bears a insightful effect on the resulting spectrum quality. Therefore, the sample prepared provides a spectrum where useful information is retained, not lost, or obscured. Sample preparation thus stands critical in the analysis and integration of NMR results. ScopeThe scope of work will cover sample Purification, given that this determines the resulting spectrum, sample collection, and sample Preparation for NMR integration and Analysis.

NMR spectrum is the basic source of data that relates to the structure of the compound. Therefore, it is required that the spectrum analysis be done properly to obtain or get a good and reasonable data set for analysis. Under any particular circumstance, the preparation of the NMR sample is not allowed at the NMR room, thus the lab is used or a special lab. A solid or pure liquid can not just be put into the NMR. A series of preparation steps needs to be followed to prepare the sample thus covering the scope of work to be done.

If one has a liquid to be analyzed, one or two drops of the liquid are put on a clean NMR tube retrieved from the oven. Approximately 3fingers worth of the deuterated (CDCl3) solvent is added to the tube. This procedure forms the scope of work because the NMR cannot work if the solvent (deuterated) is not used. When one has a solid, it becomes easier to put the solid into the small test tube and almost the same amount of deuterated solvent added and the solid allowed dissolving in the solvent before transferring to the NMR tube (Weizmann Institute of Science,2009).

QC Procedure The quality control procedure for the preparation of the sample comprises of a number of steps that have to be observed in order to obtain better results. The steps involve:Using the correct or right quantity of the material- for the proton spectra of organic compounds apart from polymers, the required material quantity is approximately 5 to 25mg.Removing all the solid particles because they distort the magnetic field homogeneity given that the magnetic susceptibly of a particle is different from that of the solutionMaking samples to the right or correct depth (Bruker is 5 mm probes, and coil length is 12 mm.

the solvent length is 36 mm solvent translating to 0.5 mL solvent. Using deuterated solvents because the samples have to be prepared using approximately 5-10% of deuterated solvents.Using clean Caps and Tubes-Tubes have to be capped and the caps treated as the tubes. The NMR tubes having broken or chipped tops should not be used. Labeling the samples Using an internal reference such as TMSDegassing the samples or having oxygen removed from the samplesBibliographyWeizmann Institute of Science., 2009. Sample preparation & NMR Tubes.

[Online] Available at: < http://www.weizmann.ac.il/Chemical_Research_Support/highres_NMR/ internal/Sample_preparation_&_NMR_Tubes.html> [Accessed November 14, 2012]