title: Minimizing matrix effect by femtosecond laser ablation and ionization in elemental determination.
abstract: Matrix effect is unavoidable in direct solid analysis, which usually is a leading cause of the nonstoichiometric effect in quantitative analysis. In this research, experiments were carried out to study the overall characteristics of atomization and ionization in laser-solid interaction. Both nanosecond (ns) and femtosecond (fs) lasers were applied in a buffer-gas-assisted ionization source coupled with an orthogonal time-of-flight mass spectrometer. Twenty-nine solid standards of ten different matrices, including six metals and four dielectrics, were analyzed. The results indicate that the fs-laser mode offers more stable relative sensitivity coefficients (RSCs) with irradiance higher than 7 × 10(13) W·cm(-2), which could be more reliable in the determination of element composition of solids. The matrix effect is reduced by half when the fs-laser is employed, owing to the fact that the fs-laser ablation and ionization (fs-LAI) incurs an almost heat-free ablation process and creates a dense plasma for the stable ionization.
authors.affiliation: Department of Chemistry, Key Laboratory of Analytical Sciences, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, Fujian, 361005 China.
authors.forename: Bochao
authors.initials: B
authors.lastname: Zhang
authors.forename: Miaohong
authors.initials: M
authors.lastname: He
authors.forename: Wei
authors.initials: W
authors.lastname: Hang
authors.forename: Benli
authors.initials: B
authors.lastname: Huang
mesh_terms: D007477:Ions / Q000737:chemistry; D007834:Lasers; D008670:Metals / Q000032:analysis* / Q000737:chemistry; D012987:Soil / Q000737:chemistry*; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; D013440:Sulfides / Q000032:analysis* / Q000737:chemistry; D013997:Time Factors
chemical_list: D007477:Ions; D008670:Metals; D012987:Soil; D013440:Sulfides