MALDI TOF-TOF characterization of a light stabilizer polymer contaminant from polypropylene or polyethylene plastic test tubes.
Disposable plasticware such as plastic test tubes are routinely used in all proteomics laboratories. Additives in polymers are used to protect them against oxygen or ultraviolet (UV) light degradation. Hindered amine light stabilizers (HALSs) are of utmost importance in modern polyolefin (polypropylene, polyethylene) stabilization. In this article, we demonstrate that the manufacturing polymeric agent: poly-(N-beta-hydroxyethyl-2,2,6,6-tetramethyl-4-hydroxy-piperidinyl succinate), known as Tinuvin-622 or Lowilite 62, from the HALS family, leaches from laboratory polypropylene or polyethylene plastic test tubes into the standard solvents for sample preparation. The analysis of these polluted samples by matrix-assisted laser desorption/ionisation-time of flight (MALDI-TOF) mass spectrometry, in the positive mode, shows highly contaminated mass spectra, due to the high sensitivity of this technique. These contaminants have mass range and mass defect similar to those of peptides arising from the digestion of a protein in a conventional proteomics study. Therefore, they can be really harmful for proteomics studies, leading to misattributions, preventing any protein identification. In this article, an MS and MS/MS fingerprint of this pollutant is given and some pieces of advice to avoid it are proposed.
Sachon
Emmanuelle
E
UPMC, 7-9 quai Saint Bernard, bâtiment A, Plateforme de Protéomique et spectrométrie de masse, IFR83, 75005 Paris, France. Emmanuelle.Sachon@snv.jussieu.fr
Matheron
Lucrèce
L
Clodic
Gilles
G
Blasco
Thierry
T
Bolbach
Gérard
G
D000588:Amines / Q000737:chemistry; D004209:Disposable Equipment; D011091:Polyesters / Q000737:chemistry*; D020959:Polyethylene / Q000737:chemistry*; D011126:Polypropylenes / Q000737:chemistry*; D040901:Proteomics; D012680:Sensitivity and Specificity; D012710:Serum Albumin, Bovine; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization / Q000379:methods*
D000588:Amines; D011091:Polyesters; D011126:Polypropylenes; C421040:poly-(N-hydroxyethyl-2,2,6,6-tetramethyl-4-hydroxypiperidyl succinate); D012710:Serum Albumin, Bovine; D020959:Polyethylene