scholarly journals Low-field NMR for quality control on oils

2019 ◽  
Vol 57 (10) ◽  
pp. 777-793 ◽  
Author(s):  
Thomas Rudszuck ◽  
Eva Förster ◽  
Hermann Nirschl ◽  
Gisela Guthausen
Keyword(s):  
Quality Control ◽  
Low Field ◽  
Low Field Nmr

scholarly journals Qualification of automated low-field NMR relaxometry for quality control of polymers in a production setting

2007 ◽  
Vol 26 (8) ◽  
pp. 1015-1024 ◽  
Author(s):  
Sarah C. Chinn ◽  
Angela Cook-Tendulkar ◽  
Robert Maxwell ◽  
Hilary Wheeler ◽  
Mark Wilson ◽  
...  
Keyword(s):  
Quality Control ◽  
Low Field ◽  
Nmr Relaxometry ◽  
Low Field Nmr

Is Low-field NMR a Complementary Tool to GC-MS in Quality Control of Essential Oils? A Case Study: Patchouli Essential Oil

Planta Medica ◽  
2018 ◽  
Vol 84 (12/13) ◽  
pp. 953-963 ◽  
Author(s):  
Andre Krause ◽  
Yu Wu ◽  
Runtao Tian ◽  
Teris van Beek
Keyword(s):  
Quality Control ◽  
Essential Oil ◽  
Essential Oils ◽  
1H Nmr ◽  
Nmr Spectra ◽  
Control Technique ◽  
Test Case ◽  
Low Field ◽  
Low Field Nmr ◽  
Quality Control Technique

AbstractHigh-field NMR is an expensive and important quality control technique. In recent years, cheaper and simpler low-field NMR has become available as a new quality control technique. In this study, 60 MHz 1H-NMR was compared with GC-MS and refractometry for the detection of adulteration of essential oils, taking patchouli essential oil as a test case. Patchouli essential oil is frequently adulterated, even today. In total, 75 genuine patchouli essential oils, 10 commercial patchouli essential oils, 10 other essential oils, 17 adulterants, and 1 patchouli essential oil, spiked at 20% with those adulterants, were measured. Visual inspection of the NMR spectra allowed for easy detection of 14 adulterants, while gurjun and copaiba balsams proved difficult and one adulterant could not be detected. NMR spectra of 10 random essential oils differed not only strongly from patchouli essential oil but also from one another, suggesting that fingerprinting by low-field NMR is not limited to patchouli essential oil. Automated chemometric evaluation of NMR spectra was possible by similarity analysis (Mahalanobis distance) based on the integration from 0.1 – 8.1 ppm in 0.01 ppm increments. Good quality patchouli essential oils were recognised as well as 15 of 17 deliberate adulterations. Visual qualitative inspection by GC-MS allowed for the detection of all volatile adulterants. Nonvolatile adulterants, and all but one volatile adulterant, could be detected by semiquantitation. Different chemometric approaches showed satisfactory results. Similarity analyses were difficult with nonvolatile adulterants. Refractive index measurements could detect only 8 of 17 adulterants. Due to advantages such as simplicity, rapidity, reproducibility, and ability to detect nonvolatile adulterants, 60 MHz 1H-NMR is complimentary to GC-MS for quality control of essential oils.

Ultra-low field NMR measurements of liquids and gases with short relaxation times

2006 ◽  
Vol 183 (1) ◽  
pp. 134-141 ◽  
Author(s):  
P.L. Volegov ◽  
A.N. Matlachov ◽  
R.H. Kraus
Keyword(s):  
Relaxation Times ◽  
Low Field ◽  
Low Field Nmr
Sign in / Sign up

Export Citation Format

Share Document