scholarly journals Discovery of Unexpected Sphingolipids in Almonds and Pistachios with an Innovative Use of Triple Quadrupole Tandem Mass Spectrometry

Foods ◽  
2020 ◽  
Vol 9 (2) ◽  
pp. 110 ◽  
Author(s):  
Federico Maria Rubino ◽  
Michele Dei Cas ◽  
Monica Bignotto ◽  
Riccardo Ghidoni ◽  
Marcello Iriti ◽  
...  
Keyword(s):  
Mass Spectrometry ◽  
Tandem Mass Spectrometry ◽  
Neutral Loss ◽  
Spectrometric Method ◽  
Total Lipid Extract ◽  
Tandem Mass ◽  
Mass Spectrometric Method ◽  
Triple Quadrupole ◽  
Loss Experiment ◽  
Long Chain

The densely packed storage of valuable nutrients (carbohydrates, lipids, proteins, micronutrients) in the endosperm of nuts and seeds makes the study of their complex composition a topic of great importance. Ceramides in the total lipid extract of some ground almonds and pistachios were searched with a systematic innovative discovery precursor ion scan in a triple quadrupole tandem mass spectrometry, where iso-energetic collision activated dissociation was performed. Five descriptors were used to search components with different C18 long chain bases containing different structural motifs (d18:0, d18:1, d18:2, t18:0, t18:1). The presence of hexoside unit was screened with a specific neutral loss experiment under iso-energetic collision activated dissociation conditions. The discovery scans highlighted the presence of two specific hexosyl-ceramides with a modified sphingosine component (d18:2) and C16:0 or C16:0 hydroxy-fatty acids. The hexosyl-ceramide with the non-hydroxylated fatty acid seemed specific of pistachios and was undetected in almonds. The fast and comprehensive mass spectrometric method used here can be useful to screen lipid extracts of several more seeds of nutraceutical interest, searching for unusual and/or specific sphingosides with chemically decorated long chain bases.

Rapid diagnosis of phenylketonuria by quantitative analysis for phenylalanine and tyrosine in neonatal blood spots by tandem mass spectrometry

1993 ◽  
Vol 39 (1) ◽  
pp. 66-71 ◽  
Author(s):  
D H Chace ◽  
D S Millington ◽  
N Terada ◽  
S G Kahler ◽  
C R Roe ◽  
...  
Keyword(s):  
Mass Spectrometry ◽  
Tandem Mass Spectrometry ◽  
Neonatal Screening ◽  
Screening Method ◽  
Dried Blood Spots ◽  
Spectrometric Method ◽  
Tandem Mass ◽  
Mass Spectrometric Method ◽  
Blood Spots ◽  
Minimal Sample

Abstract A new method for quantifying specific amino acids in small volumes of plasma and whole blood has been developed. Based on isotope-dilution tandem mass spectrometry, the method takes only a few minutes to perform and requires minimal sample preparation. The accurate assay of both phenylalanine and tyrosine in dried blood spots used for neonatal screening for phenylketonuria in North Carolina successfully differentiated infants who had been classified as normal, affected, and falsely positive by current fluorometric methods. Because the mass-spectrometric method also recognizes other aminoacidemias simultaneously and is capable of automation, it represents a useful development toward a broad-spectrum neonatal screening method.

scholarly journals Mass spectrometric analysis of prenyl phosphates and their glycosylated forms.

1994 ◽  
Vol 41 (3) ◽  
pp. 345-349 ◽  
Author(s):  
B A Wolucka ◽  
E De Hoffmann
Keyword(s):  
Mass Spectrometry ◽  
Tandem Mass Spectrometry ◽  
Impact Ionization ◽  
Negative Ions ◽  
Mass Range ◽  
Mass Spectrometric ◽  
Spectrometric Method ◽  
Spectrometric Analysis ◽  
Tandem Mass ◽  
Mass Spectrometric Method

Three different mass spectrometric method suitable for the analysis of polyprenyl and dolichyl phosphates and their glycosylated forms are described. Fast atom bombardment mass spectrometry (FAB MS) of glycosyl monophosphopolyprenols produces negative ions characteristic of the intact molecule. Tandem mass spectrometry of (M-H)- anions allows the determination of masses of both glycosyl and lipid moieties. Thus, for example, FAB-MS/MS of a mixture of native glycosyl monophosphopolyprenols isolated from ethambutol-treated Mycobacterium smegmatis enabled us to detect two novel pentosyl monophosphopolyprenols. Two other methods are proposed for the analysis of prenyl phosphates, as these compounds do not produce fragments in FAB-MS/MS at low collisional energy. By Desorption Electron Impact ionization (DEI) an intense (M-H3PO4)+ ion as well as fragments corresponding to the successive loss of isoprene residues (68 Da) can be observed. Alternatively, Desorption Chemical Ionization yields ions corresponding to the loss of 66, 78 and 98 Da (i.e. of a part or the entire phosphate moiety) of a prenyl phosphate molecule. Tandem mass spectrometry of the (M-H-98)- ion gives a series of intense fragments differing by 68 mass units over the whole mass range.

A Novel Simultaneous Estimation of Sofosbuvir and Velpatasvir in Human Plasma by Liquid Chromatography Tandem-Mass Spectrometry after Protein Precipitation Method

2019 ◽  
Vol 15 (7) ◽  
pp. 710-715
Author(s):  
S.T. Narenderan ◽  
Basuvan Babu ◽  
T. Gokul ◽  
Subramania Nainar Meyyanathan
Keyword(s):  
Mass Spectrometry ◽  
Tandem Mass Spectrometry ◽  
Human Plasma ◽  
Multiple Reaction Monitoring ◽  
Simultaneous Estimation ◽  
Pharmacokinetic Studies ◽  
Tandem Mass ◽  
Mass Spectrometric Method ◽  
Highly Sensitive ◽  
Tandem Mass Spectrometric

Objective: The aim of the present work is to achieve a novel highly sensitive chromatographic method for the simultaneous determination of hepatitis C agents, sofosbuvir and velpatasvir from human plasma using ritonavir as an internal standard. Methods: Chromatographic separation was achieved using Hypersil C18 column (50mm x 4.6mm, 3μm) with an isocratic elution mode using the mobile phase composition 10 mM ammonium formate buffer (pH 5.0): acetonitrile (20:80 v/v) pumped at a flow rate of 0.5 ml/min. The detection was carried out by tandem mass spectrometry using Multiple Reaction Monitoring (MRM) positive Electrospray Ionization (ESI) with proton adducts at m/z 530.10 > 243.10, 883.40 > 114.0 and 721.25 > 197.0. Results: The method validated as per USFDA guidelines with respect to linearity, accuracy, and precision was found to be acceptable over the concentration range of 0.2–2000 ng/ml and 5-2000 ng/ml for sofosbuvir and velpatasvir respectively and the method was found to be highly sensitive and selective. Conclusion: The developed tandem mass spectrometric method is robust and can be applied for the monitoring of plasma levels of the analyzed drug in preclinical and clinical pharmacokinetic studies.

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