title: Lipidomic fingerprint of almonds (Prunus dulcis L. cv Nonpareil) using TiO₂ nanoparticle based matrix solid-phase dispersion and MALDI-TOF/MS and its potential in geographical origin verification.
abstract: A matrix solid-phase dispersion (MSPD) procedure with titanium dioxide (TiO2) nanoparticles (NP) as sorbent was developed for the selective extraction of phospholipids from almond samples, and matrix-assisted laser desorption ionization-time-of-flight mass spectrometry (MALDI-TOF/MS) was employed for analysis. A remarkable increase in the signals of phospholipid accompanied by a decrease in those of triacylglycerols and diacylglycerols was observed in the relevant mass spectra. The proposed method was applied to five batches of almonds originating from four geographical areas, whereas principal component analysis (PCA) was utilized to normalize the relative amounts of the identified phospholipid species. The results indicated that the lipidomic fingerprint of almonds was successfully established by the negative ion mode spectrum, and the ratio of m/z 833.6 to 835.6 as well as m/z 821.6 could be introduced as potential markers for the differentiation of the tested almonds with different geographical origins. The whole method is of great promise for selective separation of phospholipids from nonphospholipids, especially the glycerides, and superior in fast screening and characterization of phospholipids in almond samples.
authors.affiliation: Department of Chemistry and Biology, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong SAR, China.
authors.forename: Qing
authors.initials: Q
authors.lastname: Shen
authors.forename: Wei
authors.initials: W
authors.lastname: Dong
authors.forename: Mei
authors.initials: M
authors.lastname: Yang
authors.forename: Linqiu
authors.initials: L
authors.lastname: Li
authors.forename: Hon-Yeung
authors.initials: HY
authors.lastname: Cheung
authors.forename: Zhifeng
authors.initials: Z
authors.lastname: Zhang
mesh_terms: D000327:Adsorption; D005843:Geography; D008055:Lipids / Q000737:chemistry* / Q000302:isolation & purification; D053758:Nanoparticles / Q000737:chemistry; D010936:Plant Extracts / Q000737:chemistry* / Q000302:isolation & purification; D027861:Prunus / Q000737:chemistry*; D052616:Solid Phase Extraction / Q000295:instrumentation / Q000379:methods*; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; D053719:Tandem Mass Spectrometry / Q000379:methods*; D014025:Titanium / Q000737:chemistry
chemical_list: D008055:Lipids; D010936:Plant Extracts; C009495:titanium dioxide; D014025:Titanium