Solvent‐free sample introduction for supercritical fluid chromatography using polymer coated fibers

Abstract

Abstract.A solvent-free sample introduction method for supercritical fluid chromatography that uses polymer coated fused silica fibers results in very stable baseline and high efficiency separations. The method has two steps: first, a fiber is exposed to a prepared mixture of target analytes or a sample so that the polymeric coating absorbs analytes, and second, the fiber is placed inside a piece of tubing connected to the column of a supercritical fluid chromatograph. The supercritical fluid carrier extracts analytes from the coating and transfers them onto the head of the column. Pressure programmed separation follows. The method was tested on high molecular weight and polar analytes using 100 and 50 pm i.d. capillary columns. Fibers with a polydimethylsiloxane coating were used to extract hydrophobic analytes, and fibers with a polyacrylate coating were used to extract more polar compounds.

Supercritical Fluid Chromatography and Extraction

“…Hirata and Pawliszyn described an injection procedure in which a polymercoated fiber is exposed to liquid sample to absorb solutes. The fiber is then removed and placed in a piece of tubing for desorption to an OT-SFC column to accomplish a solvent-free solute transfer (87). Ullsten and Markides combined solid-phase extraction and SFE to introduce samples dissolved in polar solvents onto an SFC column.…”

Analysis of biological samples using solid-phase microextraction

“…It has been used routinely, in combination with gas chromatography (GC), and successfully applied to a wide variety of compounds, especially for the extraction of volatile and semivolatile organic compounds from environmental, biological and food samples [3][4][5][6][7]. SPME was also introduced for direct coupling with HPLC and LC-MS in order to analyze weakly volatile or thermally labile compounds not amenable to GC or GC-MS [5,7] and with supercritical fluid extraction [8]. SPME has successfully been coupled to capillary electrophoresis (CE) [9,10] and packed column supercritical fluid chromatography (PCSFC) [11].…”

Preparation and application of poly(dimethylsiloxane)/β‐cyclodextrin solid‐phase microextraction fibers

“…It is convenient and solvent-free, and easily utilized with GC, HPLC, and other methods [2][3][4]. The technique has been successfully applied to analyze various compounds in environmental, industrial, pharmaceutical, and clinical samples [5].…”