Effect of matrix and solvent on the analysis of novel poly(phenylenevinylene) derivatives by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry

Six novel poly(phenylenevinylene) (PPV) derivatives carrying butoxy or myrtanyl groups, including poly(2-butoxy-m-phenylenevinylene) (Bu-MPV), poly(2,5-dibutoxy-p-phenylenevinylene-alter-p-phenylenevinylene) (Bu-PPPV), poly(2,5-dibutoxy-p-phenylenevinylene-alter-m-phenylenevinylene) (Bu-PMPV), poly(2-myrtanyl-m-phenylenevinylene) (Myr-MPV), poly(2,5-dimyrtanyl-p-phenylenevinylene-alter-p-phenylenevinylene) (Myr-PPPV), and poly(2,5-dimyrtanyl-p-phenylenevinylene-alter-m-phenylenevinylene) (Myr-PMPV), were characterized by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOFMS). The repeat unit mass and the end-group structures of each sample were obtained. Distinctly different spectra with different ion series and/or different ion signal intensities were observed for the analytes Bu-MPV, Myr-MPV, Bu-PPPV, Myr-PPPV and Myr-PMPV when different matrices were used, and different ion series were acquired when different solvents were used for Myr-PPPV and Myr-PMPV. The results show that the PPV oligomers with different shapes and/or with different end groups can be selectively desorbed and ionized in MALDI by using different matrices.