Injection-port derivatization coupled to GC–MS/MS for the analysis of glycosylated and non-glycosylated polyphenols in fruit samples

Abstract

Polyphenols, including glycosylated polyphenols, were analyzed via a procedure based on injection-port derivatization coupled to gas chromatography-tandem mass spectrometry (GC-MS/MS). The polyphenols in lyophilized fruit samples were extracted with an acidified MeOH mixture assisted by ultrasound. Samples were dried under vacuum, and carbonyl groups were protected with methoxylamine. Free hydroxyl groups were subsequently silylated in-port. Mass fragmentations of 17 polyphenol and glycosylated polyphenol standards were examined using Multiple Reaction Monitoring (MRM) as the acquisition mode. Furthermore, in-port derivatization was optimized in terms of optimal injection port temperature, derivatization time and sample: N-methyl-N-(trimethylsilyl)trifluoroacetamide (MSTFA) volume ratio. A C18 solid-phase-extraction clean-up method was used to reduce matrix effects and injection liner degradation. Using this clean-up method, recoveries for samples spiked at 1 and 10μg/g ranged from 52% to 98%, depending on the chemical compound. Finally, the method was applied to real fruit samples containing the target compounds. The complete chromatographic runtime was 15min, which is faster than reported for recent HPLC methods able to analyze similar compounds.

Rapid characterization of the chemical constituents of Cortex Fraxini by homogenate extraction followed by UHPLC coupled with Fourier transform ion cyclotron resonance mass spectrometry and GC–MS

“…4B). Peak 33 displayed [M-H] − at m/z 539.17701, and the formula was calculated as C 25 Following comparison with the literature [27], peak 33 was identified as oleuropein. On the basis of the fragmentation patterns, peaks 13, 28, 29, 30, 31, and 32 in Fig.…”

“…In addition, it can provide information about the isotopic abundancy of ions, and it is helpful for determining the structures of chemical constituents. GC–MS has high resolution and sensitivity, and can be used to separate and characterize ingredients by converting the analytes into volatile compounds by silylation .…”

Targeted analysis of microbial-generated phenolic acid metabolites derived from grape flavanols by gas chromatography-triple quadrupole mass spectrometry

“…LLODs were in the range of 0.24–6.18 ng/mL and LLOQs were 0.48–12.37 ng/mL. These values demonstrate excellent sensitivity of the proposed method, especially when compared to other GC-MS methods for analyzing phenolic acid metabolites derived from dietary polyphenols [21,22]. For example, Grün et al analyzed microbial-generated phenolic acid metabolites present in biofluids from human subjects treated with a grape polyphenol-rich extract and reported much higher LLODs, ranging from 50 to 50,000 ng/mL [21].…”

Advanced Analytical Approaches for the Analysis of Polyphenols in Plants Matrices—A Review

“…Although the use of GC coupled with MS and tandem MS-MS has been proven a powerful analytical tool for natural products' characterization [117], there is a limited range of polyphenolic compounds that can be analyzed by GC-MS methods. Phenolic acids, phenolic aldehydes, ketones and phenolic alcohols were recently analyzed by GC-MS in wild plant fruits [117], fruit samples [36,118], Curcuma caesia Roxb [119], Kodo millet (Paspalum scrobiculatum) [120], and Scambiosa Columbabria L. [121]. Although newer twodimensional GC x GC systems improved the separation performance and resolution [122], currently, the GC-MS technique is less commonly employed mainly because complex sample pre-treatments are required to increase the volatility and stability of the phenolic compounds.…”