title: Trapping of wide range mass-to-charge ions and dependence on matrix amount in internal source MALDI-FTMS.
abstract: Internal ionization source MALDI-FTMS shows clear variation of number average molecular weight (M(n)) for an equimolar mixture of four PEG polymers (PEG 2000, PEG 4000, PEG 6000, PEG 8000) when the 2,5-dihydroxy benzoic acid (DHB) matrix to PEG ratio is varied or the laser power is changed. As the matrix to analyte ratio is increased, the analyte signal of higher molecular mass ions increases and the signal of lower mass ions decreases. Laser power dependence studies show a similar trend. Possible explanations for these observations are discussed.
authors.affiliation: Department of Chemistry and Biochemistry, University of Arkansas, Fayetteville, AR 72701, USA.
authors.forename: Arwah J
authors.initials: AJ
authors.lastname: Jaber
authors.forename: Jacob
authors.initials: J
authors.lastname: Kaufman
authors.forename: Rohana
authors.initials: R
authors.lastname: Liyanage
authors.forename: Eugenia
authors.initials: E
authors.lastname: Akhmetova
authors.forename: Samuel
authors.initials: S
authors.lastname: Marney
authors.forename: Charles L
authors.initials: CL
authors.lastname: Wilkins
mesh_terms: D000465:Algorithms; D001565:Benzoates / Q000737:chemistry*; D007477:Ions; D008970:Molecular Weight; D011092:Polyethylene Glycols / Q000032:analysis* / Q000737:chemistry*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013048:Specimen Handling / Q000379:methods; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization / Q000379:methods*; D017550:Spectroscopy, Fourier Transform Infrared / Q000379:methods*; D055672:Static Electricity
chemical_list: D001565:Benzoates; D007477:Ions; D011092:Polyethylene Glycols