An optimized and validated 1H NMR method for the quantification of α-pinene in essentials oils

• Published in: Talanta (Oxford) 2016-04, Vol.150, p.97-103
• Main Authors: Cerceau, Cristiane I., Barbosa, Luiz C.A., Filomeno, Claudinei A., Alvarenga, Elson S., Demuner, Antônio J., Fidencio, Paulo H.
• Format: Article
• Language: English
• Subjects: Essential oils; Gas chromatography; Quantitative nuclear magnetic resonance; α-Pinene
• ISSN: 0039-9140; 1873-3573
• DOI: 10.1016/j.talanta.2015.10.087

The authenticity and composition of commercial essential oils requires strict quality control. Due to the importance of α-pinene containing essential oils, a rapid and efficient method for quantification of this terpene in oils of eucalyptus, pink pepper and turpentine using 1H NMR was developed and validated. All evaluated parameters (selectivity, linearity, accuracy/precision, repeatability, robustness, stability of analyte and internal standard in solutions) showed satisfactory results. The limit of detection (LOD) and limit of quantification (LOQ) were 0.1 and 2.5mg respectively. These values indicated that α-pinene was detected in 35mg samples containing at least 0.3% of this compound. In addition, a minimum of 8% of α-pinene in the sample was required for quantification. Furthermore, the standard deviations found in the 1H NMR methodology were less than 1% and were lower than those obtained by gas chromatographic analysis. Statistical tests have shown that the results obtained by 1H NMR methodology are similar to those obtained by GC-FID technique using external and internal standardization and normalization within 95% confidence. R&R values lower than 10% have shown that all the methods are appropriate and the 1H NMR method is suitable for quantification of α-pinene in samples of essential oils since this method possessed the smallest R&R (1.81) value. [Display omitted] •1H NMR can be efficiently used to quantify α-pinene in essential oils.•1H NMR spectroscopy is used for quality control of essential oils.•A fast method for analysis of α-pinene in essential oils using 1H NMR was developed.•Quantification of α-pinene by 1H NMR is comparable to GC–MS and GC-FID.