Compound-specific carbon isotope ratio analysis is a promising tool to assess the origin and fate of organic contaminants in groundwater. The aim of this study was to develop and evaluate a reliable, fast method to determine carbon isotope ratios of chlorinated methanes, ethanes, and ethenes in aqueous samples. Direct solid-phase microextraction (dSPME) and headspace solid-phase microextraction...

We report the application of the dispersive liquid-liquid microextraction coupled to hollow-fibre membrane-assisted liquid-phase microextraction and its application for extraction of atrazine and triclosan. Under optimum conditions, namely, 25 μL of a 1 : 4 chlorobenzene : ethyl acetate mixture dispersed in 1 mL of aqueous sample, 10% (m/v) NaCl, a magnetic stirrer speed at 600 rpm, and 10 minu...

Sample preparation is important for the isolation and concentration of desired trace components from complex matrices. Sample preparation is the most labor-intensive and error-prone process in analytical methodology, and greatly influences the reliable and accurate determination of analytes. The integration of sample preparation with various analytical instruments is most conveniently achieved ...

Abstract Solid-phase microextraction (SPME) is an analytical method for of analytes, in which the analytes bind to sorbent on surface SPME fiber. Many types chemical agents are used as sorbent; however, many these sorbents cause secondary contamination or not cost-effective. Here, aqueous extract Ferula gummosa was evaluated potential source simultaneous morphine and codeine. For this purpose, ...

In this paper, we analyze the electromagnetic mode structure of an OmniGuide fiber-a hollow dielectric waveguide in which light is confined by a large index-contrast omnidirectional dielectric mirror. In particular, we find that the modes in an OmniGuide fiber are similar to those in a hollow metallic waveguide in their symmetries, cutoff frequencies, and dispersion relations. We show that the ...

Liquid-liquid extraction or solid-phase extraction followed by gas chromatography (GC) or high-performance liquid chromatography are traditional herbicide residue determination methods for environmental samples. Solid-phase microextraction (SPME) is a solventless, fast, and sensitive alternative herbicide residue extraction method that can be applied to numerous environmental matrices. The obje...

Zirconia bio-ceramic hollow fiber membranes were developed using a sequence of mixing, extrusion, phase inversion and sintering steps. ZrO2 p g m m w e f ©

We introduce digital microfluidic interface between solid-phase microextraction (SPME) and liquid chromatography. In the new system, a SPME fiber is used to extract analytes from a complex sample, and is then inserted into a DMF device. Solvent droplets are then used to extract analytes from the fiber with continuous actuation, followed by analysis with liquid chromatography (LC) and mass spect...

Hollow fibre cell fishing with HPLC (HFCF-HPLC) based on the human ovarian cancer cell line SKOV-3, human renal tubular cell line ACHN or hepatoma cell line HepG-2 was employed to screen active groups of coumarin and volatile oil in Radix angelicae sinensis, Radix angelicae dahuricae and Fructus citri sarcodactylis. Simultaneously, hollow fibre liquid phase microextraction with HPLC (HFLPME-HPL...