Polymer-Coated Fiber-Packed Capillary as the Sample Preparation Medium in Liquid Chromatography: Heart-Cutting Analysis of Phthalates in Aqueous Matrices

Abstract

Preconcentration of aqueous solution of aromatic compounds was successfully carried out with an extraction capillary packed with a bundle of polymer-coated filaments. The extracted analytes were sequentially eluted with a flow of pure water using programmed temperature elevation of the extraction capillary. The results clearly suggest that the polymer-coated fiber-packed capillary could be employed as a sample preparation medium for the analysis of aqueous matrices. The fraction of interest could be transferred to conventional microcolumn liquid chromatography (LC) allowing a heart cutting analysis of aqueous matrices. Stability of the fiber-packed capillary was confirmed with pure water as the mobile phase at elevated temperatures.

Miniaturization for the Development of High Performance Separation Systems

“…Miniaturized sample preparation with fiber-packed capillary and the effective coupling to microscale separation methods will suggest a future possibility to other related applications, such as an interface between two-dimensional chromatographic separations [101][102][103][104][105]. The applications of polymer-coated and surface-derivatized fibrous materials in miniaturized sample preparation process also demonstrate a possibility to the employment of similar fibrous separation media as the new format of the stationary phase materials in various chromatographic techniques.…”

Preconcentration of Aromatic Compounds in Aqueous Samples with a Polymer-coated Fiber-packed Capillary and Subsequent Temperature-programmed Elution with Water for Pseudo-2D LC Separations

“…The bundle of Zylon originally consisted of 166 fine filaments, and the number of the filaments per bundle was adjusted as described below. On the basis of preliminary results, 25,26 an HR-17 (50%-phenyl-50%-methylpolysiloxane, Shinwa Chemical Industries, Kyoto, Japan) was employed as the material of polymer-coating onto Zylon filaments.…”

“…The oven temperature was programmed from 30 to 300 C at 2 C min -1 , and then held at the final temperature for about 10 h. After the above-mentioned washing process, a solution of the polymeric coating material (HR-17) in n-hexane containing a cross-linking reagent was pumped through the packed capillary. The concentration of the polymer solution was optimized as 0.5 wt% on the basis of preliminary experiments, 25,26 as the first choice, to evaluate the fundamental extraction/retention characteristics. Next to the pumping of a polymer solution of 5 mL, N2 flow through the capillary was maintained for more than 5 h. The capillary was then installed in the GC oven again, and the temperature was elevated with a program from 40 to 300 C at 0.5 C min -1 , followed by extended heating for more than 60 h to make sure of successful coating.…”

Spherical Polyimide Particles as a Novel Stationary Phase in Liquid Chromatography

“…In terms of the use of polymer-based materials in LC, spherical particles of the various polymers and copolymers have been mainly studied as the stationary phase, although fibrous polymeric materials were also introduced as a stationary phase in gas chromatography [4][5][6][7][8][9][10][11][12][13][14] and LC [13][14][15][16][17][18][19][20][21][22][23][24][25][26], along with an extraction medium in sample preparation techniques for liquid samples [27][28][29][30][31][32][33][34][35][36][37][38][39] and gas samples [40][41][42][43][44][45]. In our previous investigation, a spherical polyimide (PI) particles have been introduced as a novel extraction medium in miniaturized sample preparation technique [45,46].…”