Identification and Quantification of Dimethylamylamine in Geranium by Liquid Chromatography Tandem Mass Spectrometry

Abstract

A sensitive and reliable method of liquid chromatography–electrospray ionization/tandem mass spectrometry (LC-ESI/MS/ MS) was developed and validated for determining 1,3-dimethylamylamine (1,3-DMAA) and 1,4-dimethylamylamine (1,4-DMAA) in geranium plants (Pelargonium graveolens). The sample was extracted with 0.5 M HCl and purified by liquid-liquid partition with hexane. The parameters for reverse-phase (C18) LC and positive ESI/MS/MS were optimized. The matrix effect, specificity, linearity, precision, accuracy and reproducibility of the method were determined and evaluated. The method was linear over a range of 0.10–10.00 ng/mL examined, with R2 of 0.99 for both 1,3-DMAA and 1,4-DMAA. The recoveries from spiked concentrations between 5.00–40.00 ng/g were 85.1%–104.9% for 1,3-DMAA, with relative standard deviation (RSD) of 2.9%–11.0%, and 82.9%–101.8% for 1,4-DMAA, with RSD of 3.2%–11.7%. The instrument detection limit was 1–2 pg for both DMAAs. The quantification limit was estimated to be 1–2 ng/g for the plant sample. This method was successfully applied to the quantitative determination of 1,3- and 1,4-DMAA in both geranium plant and geranium oil.

Analysis and Confirmation of 1,3-DMAA and 1,4-DMAA in Geranium Plants Using High Performance Liquid Chromatography with Tandem Mass Spectrometry at ng/g Concentrations

“…There has been significant discussion of 1,3-dimethylamylamine (1,3-DMAA) in the literature concerning the presence of 1,3-DMAA in geranium plants ( Pelargonium graveolens ) 1–6. 1,3-DMAA, also known as 4-methyl-2-hexaneamine (MHA), 1,3-dimethylpentylamine, or 2-amino-4-methylhexane can be labeled as geranium extract in dietary supplements.…”

“…The geranium oil and plant matrix are sufficiently complex that most universal detectors, such as refractive index and flame ionization detectors, are likely to encounter significant matrix interferences. Thus, research and analytical effort for 1,3-DMAA analysis has focused on GC-MS1,3–5 and LC-MS/MS 1,2,4–6 analysis protocols for matrices, such as urine, geranium oil extracts and geranium plants.…”

Identification and quantification of 1,3-dimethylbutylamine (DMBA) from Camellia sinensis tea leaves and dietary supplements

“…More recently, ElSohly et al [10] found no DMAA in 18 Pelargonium plant samples with HPLC/MS/MS instrumentation in an international collaborative study. However, along with Ping's paper [4], three other papers have claimed to confirm the presence of DMAA in geranium [11][12][13], while all independent academic investigations have been unable to find any evidence of DMAA in http://dx.doi.org/10.1016/j.jpba.2015.07.004 0731-7085/© 2015 Elsevier B.V. All rights reserved. geranium [6][7][8]14,15].…”

“…Over the past several years, research has explored the possibility that DMAA might or might not be a natural constituent of geranium [4][5][6][7][8][9][10][11][12][13][14][15]. In 2014, Monakhova et al, [9] developed a nuclear magnetic resonance (NMR) method for the detection of DMAA based on integration of two methyl groups in the range 0.92-0.84 ppm.…”

Effects of controlled doses of Oxyelite Pro on physical performance in rats

“…Consequently, studies began to investigate geranium plants to identify the presence of DMAA and determine the amount of this substance. In contradiction, some studies found DMAA in geranium plants (funded by USPlabs) [11, 12] and others did not identify the DMAA being of native origin [13, 14]. In addition, the amount of DMAA found in plants was lower than the amount found in dietary supplements.…”