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Multiple Stage Tandem Mass Spectrometry for identification of plastic contaminations in blood plasma using nano electrospray ionization. Tobias Kind and Kwang-Hyeon Liu FiehnLab UC Davis 2009 http://fiehnlab.ucdavis.edu/staff/kind/Metabolomics/LipidAnalysis.
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Multiple Stage Tandem Mass Spectrometry for identification of plastic contaminations in blood plasma using nano electrospray ionization Tobias Kind and Kwang-Hyeon Liu FiehnLab UC Davis 2009 http://fiehnlab.ucdavis.edu/staff/kind/Metabolomics/LipidAnalysis File under: Anecdotal mass spectrometry CC-by Free Reuse License granted; Tobias Kind FiehnLab 2009
+ Instrumentation – robotized chip based nano electrospray ionization with linear iontrap LTQ Linear IonTrap nanoESI chip Advion NanoMate robot not shown
Full scan nanoESI positive mode with data dependent multiple stage tandem MS We will fragment this ion with the awe-inspiring power of MS/MS/MS/MS/MS/MS/MS/MS or MS8 Slowly repeat with me: MS1..MS2..MS3..MS4..MS5..MS6..MS7..MS8...
What could it be? -56.8 MS^2 precursor m/z 664.00 (ESI+) -112.76 -168.74
MS^8 (ESI+) precursor m/z 327.00
MS^8 composite tandem mass spectrumof precursor m/z 664.00 (ESI+) 56 Da 56 Da 56 Da 56 Da 56 Da Sample: KH Liu (FiehnLab)
List of ions from precursor m/z 664.00 (ESI+) Plasma_Pos_LowMS_60MSMS_CE45_01.raw Friday, April 03, 2009 MS2 precursor 664.00 |__MS3 precursor 607.32 | |__MS4 precursor 551.33 | | |__MS5 precursor 495.34 | | | |__MS6 precursor 439.26 | | | | |__MS7 precursor 383.17 | | | | | |__MS8 precursor 327.06 | | | | | | |__Composite spectrum MS8 664.00,607.32,551.33,495.34,439.26,383.17,327.06 | | | | | | |__Single spectrum MS8 664.00,607.32,551.33,495.34,439.26,383.17,327.06 (190) | | | | | |__Composite spectrum MS7 664.00,607.32,551.33,495.34,439.26,383.17 | | | | | |__Single spectrum MS7 664.00,607.32,551.33,495.34,439.26,383.17 (189) | | | | |__Composite spectrum MS6 664.00,607.32,551.33,495.34,439.26 | | | | |__Single spectrum MS6 664.00,607.32,551.33,495.34,439.26 (188) | | | |__Composite spectrum MS5 664.00,607.32,551.33,495.34 | | | |__Single spectrum MS5 664.00,607.32,551.33,495.34 (187) | | |__Composite spectrum MS4 664.00,607.32,551.33 | | |__Single spectrum MS4 664.00,607.32,551.33 (186) | |__Composite spectrum MS3 664.00,607.32 | |__Single spectrum MS3 664.00,607.32 (185) |__Single spectrum MS2 664.00 (184) List of product ions: m/z 664 , 607 ,551 ,495 ,439 ,383 ,327 accurate masses see above
Solutions – well Plasma – well Lipids use LipidMaps tools! CE(18:2(Ep)) 18 2 663.5711 0.4289 C45H75O3+ CE(18:2(Ke)) 18 2 663.5711 0.4289 C45H75O3+ CE(18:3(OH)) 18 3 663.5711 0.4289 C45H75O3+ CE(18:1(Ep))-cyclo 18 1 663.5711 0.4289 C45H75O3+ CE(18:1(Ke))-cyclo 18 1 663.5711 0.4289 C45H75O3+ CE(18:2(OH))-cyclo 18 2 663.5711 0.4289 C45H75O3+ CE(16:2(Ke,Ep2)) 16 2 663.4983 0.5017 C43H67O5+ CE(16:2(Ke2,Ep)) 16 2 663.4983 0.5017 C43H67O5+ CE(16:3(Ep,OO)) 16 3 663.4983 0.5017 C43H67O5+ CE(16:3(Ke,OO)) 16 3 663.4983 0.5017 C43H67O5+ CE(16:3(OH,Ep2)) 16 3 663.4983 0.5017 C43H67O5+ CE(16:3(OH,Ke,Ep)) 16 3 663.4983 0.5017 C43H67O5+ CE(16:3(OH,Ke2)) 16 3 663.4983 0.5017 C43H67O5+ CE(16:4(OOH,Ep)) 16 4 663.4983 0.5017 C43H67O5+ CE(16:4(OOH,Ke)) 16 4 663.4983 0.5017 C43H67O5+ CE(16:4(OH,OO)) 16 4 663.4983 0.5017 C43H67O5+ CE(16:4(OH2,Ep)) 16 4 663.4983 0.5017 C43H67O5+ CE(16:4(OH2,Ke)) 16 4 663.4983 0.5017 C43H67O5+ CE(16:5(OH,OOH)) 16 5 663.4983 0.5017 C43H67O5+ CE(16:5(OH3)) 16 5 663.4983 0.5017 C43H67O5+ CE(16:1(Ke,Ep2))-cyclo 16 1 663.4983 0.5017 C43H67O5+ CE(16:1(Ke2,Ep))-cyclo 16 1 663.4983 0.5017 C43H67O5+ CE(16:2(Ep,OO))-cyclo 16 2 663.4983 0.5017 C43H67O5+ CE(16:2(Ke,OO))-cyclo 16 2 663.4983 0.5017 C43H67O5+ CE(16:2(OH,Ep2))-cyclo 16 2 663.4983 0.5017 C43H67O5+ CE(16:2(OH,Ke,Ep))-cyclo 16 2 663.4983 0.5017 C43H67O5+ CE(16:2(OH,Ke2))-cyclo 16 2 663.4983 0.5017 C43H67O5+ CE(16:3(OOH,Ep))-cyclo 16 3 663.4983 0.5017 C43H67O5+ CE(16:3(OOH,Ke))-cyclo 16 3 663.4983 0.5017 C43H67O5+ CE(16:3(OH,OO))-cyclo 16 3 663.4983 0.5017 C43H67O5+ CE(16:3(OH2,Ep))-cyclo 16 3 663.4983 0.5017 C43H67O5+ CE(16:3(OH2,Ke))-cyclo 16 3 663.4983 0.5017 C43H67O5+ CE(16:4(OH,OOH))-cyclo 16 4 663.4983 0.5017 C43H67O5+ CE(16:4(OH3))-cyclo 16 4 663.4983 0.5017 C43H67O5+ Current mass accuracy for unit mass resolution LTQ: 78 ppm (external calibration) or 0.046 Da @ 594.46 Da for reference purposes LipidMaps Tools used with M+H
Solutions – well Plasma – well Lipids! CE(18:2(Ep)) 18 2 663.5711 0.4289 C45H75O3+ CE(18:2(Ke)) 18 2 663.5711 0.4289 C45H75O3+ CE(18:3(OH)) 18 3 663.5711 0.4289 C45H75O3+ CE(18:1(Ep))-cyclo 18 1 663.5711 0.4289 C45H75O3+ CE(18:1(Ke))-cyclo 18 1 663.5711 0.4289 C45H75O3+ CE(18:2(OH))-cyclo 18 2 663.5711 0.4289 C45H75O3+ Sphingosine CerP 18:1 644.5013 0.5013 C36H71NO6P+ Sphingosine HexCer 12:0 644.5096 0.5096 C36H70NO8+ Sphinganine Cer 24:4 644.5976 0.5976 C42H78NO3+ Problem: Our mass accuracy is 0.046 Da but the solutions are 0.5 Da difference Without Google Scholar we would be lost to search single m/z values or numbers. Still its a horrible way to do mass spectral library search. Has anybody a Google API example?
Solutions – well Plasma – well Google It! On the lipid composition of human meibum and tears: Comparative analysis of nonpolar lipids Igor A. Butovich http://www.iovs.org/cgi/content/abstract/iovs.08-1889v1 "However, rushing to this conclusion would have been a mistake because subsequent fragmentation of ion m/z 663 in sequential MSn experiments gave us the following chain of product ions differing by 56 amu: 663 (MS1) -> 607 (MS2) -> 551 (MS3) -> 495 (MS4) -> 439 (MS5) -> 383 (MS6) -> 327 (MS7) (not shown). Note that the first four ions (663, 607, 551, 495) were also easily detectable in a simple MS1 experiment (Fig. 11A) . These transformations were indicative of a sequential loss of several up to six) t-butyl groups and were formerly described for oxidized form of Irgafos 168 (C42H63O4P, Fig. 11A , inset) a polymer additive present in polyethylene and polypropylene and its derivatives." Researcher working with tears = The Dacriologist (Book by Djerassi) Dakryology, the neologism for the science of tears 10.1007/BF00137944 also CRYING: The Natural and Cultural History of Tears By Tom Lutz Norton
Solutions – well Plasma – well Plasticizers! Analysis of Additives in Polyethylene with Desorption Chemical Ionization/Tandem Mass Spectrometry S. W. CHEN and G. R. HER* Appl. Spectrosc. 47, 844-851 (1993) http://www.opticsinfobase.org/abstract.cfm?URI=as-47-6-844 Picture Source: S. W. CHEN and G. R. HER Appl. Spectrosc. 47, 844-851 (1993) Also Oxidized Naugard 524 - http://dx.doi.org/10.1016/0003-2670(95)00183-Z
Solution – probably Irganox / Irgafos contamination Our MS^8 "Lipid" Problem solved, "lipid" is oxidized plasticizer. Picture Source: Analysis of Additives in Polyethylene with Desorption Chemical Ionization/Tandem Mass Spectrometry S. W. CHEN and G. R. HER* Appl. Spectrosc. 47, 844-851 (1993) http://www.opticsinfobase.org/abstract.cfm?URI=as-47-6-844
Is the problem really solved? No, because for the formula = C42H63O4P the exact mass = 662.446397016. The [M+H]+ would be 663.4542 Da and not 664.0 In this case an ultrazoom investigation or infusion into FT-ICR-MS with resolving power 50,000 to 100,000 would probably help. CID 14572930 InChIKey: AZSKHRTUXHLAHS-UHFFFAOYSA-N MS/MS on isotopic peak, ion suppression of isobars, overlap with multiple ceramides or cholesterol and oxycholesterol species possible
Final question – How can we avoid rediscovery (reinventing the wheel)? • sharing experiments (free) • sharing mass spectra (free or sell) • putting publications into OA for easier searching • How can we prevent plasticizer contaminations? • running solvent blanks with each experiment • running methods blanks with each experiment • using only (baked) glassware • Other solutions? • library search (but compound is not in NIST) • remember the awesome power of MS/MS/MS/MS/MS/MS/MS/MS • modern iontraps are currently not used to the full extend Data Dependent • exclusion libraries for unwanted "contaminations" See: XLS supplement from Keller, B.O.; Sui, J.; Young, A.B.; Whittal, R.M. Interferences and contaminants encountered in modern mass spectrometry.