Abstract: A method of preparing a sol-gel monolithic column includes the step of forming a separation bed (14) from a sol-gel solution in a single process step. This column has improved characteristics for CEC based on its incorporated surface charge and ease of operation due to a lack of or need for end frits. Also, a second type of column includes an optical window (30) for on-column detection.

Abstract: A method is presented describing in situ preparation of the titania-based sol-gel PDMS coating and its immobilization on the inner surface of a fused silica microextraction capillary. Sol-gel titania-poly (dimethylsiloxane) (TiO2-PDMS) coating was developed for capillary microextraction (CME) to perform on-line preconcentration and HPLC analysis of trace impurities in aqueous samples. The sol-gel titania-based coatings demonstrated strong pH stability and enhanced extraction capability over other commercially available GC coatings. Extraction characteristics of a sol-gel titania-PDMS capillary remained practically unchanged after continuous rinsing with a 0.1 M NaOH solution (pH=13) for 12 hours.

Abstract: A method is presented describing in situ preparation of the titania-based sol-gel PDMS coating and its immobilization on the inner surface of a fused silica microextraction capillary. Sol-gel titania-poly (dimethylsiloxane) (TiO2-PDMS) coating was developed for capillary microextraction (CME) to perform on-line preconcentration and HPLC analysis of trace impurities in aqueous samples. The sol-gel titania-based coatings demonstrated strong pH stability and enhanced extraction capability over other commercially availble GC coatings. Extraction characteristics of a sol-gel titania-PDMS capillary remained practically unchanged after continuous rinsing with a 0.1 M NaOH solution (pH=13) for 12 hours.

Abstract: The subject invention concerns zirconia-based hybrid organic-inorganic sol-gel coating for optional use as a stationary phase in capillary microextraction (CME), gas chromatographic (GC), high performance liquid chromatography (HPLC), capillary electrophoresis (CE), capillary electrochromatography (CEC) and related analytical techniques. Sol-gel chemistry is employed to chemically bind a hydroxy-terminated silicone polymer (polydimethyldiphenylsiloxane, PDMDPS) to a sol-gel zirconia network. In one embodiment, a fused silica capillary is filled with a properly designed sol solution to allow for the sol-gel reactions to take place within the capillary. In the course of this process, a layer of the evolving hybrid organic-inorganic sol-gel polymer becomes chemically bonded to the silanol groups on the inner capillary walls.

Abstract: A novel on-line method is presented for the extraction and preconcentration of amino acids using a sol-gel coated column coupled to a conventional UV/vis detector. Extraction, stacking and focusing techniques are used in the preconcentration procedures. Sol-gel coatings are created by using N-Octadecyldimethyl[3(trimethoxysilyl)proply] ammonium chloride (C18-TMS) in the coating sol solutions. The resulting sol-gel coating carries a positive charge. For extraction, the pH of the samples is properly adjusted to impart a net negative charge to amino acids. A long plug of the sample is then passed through the sol-gel coated capillary to facilitate extraction via electrostatic interaction between the positively charged sol-gel coating and the negatively charged amino acid molecules. The focusing of the extracted amino acids is accomplished through desorption of the extracted amino acid molecules carried out by local pH change. The described procedure provides 150,000-fold enrichment effect for alanine.

Abstract: The present invention concerns a new and useful structure for forming a capillary tube, e.g. for gas chromatography, and methods for forming the capillary tube are described. The capillary tube comprises a tube structure, and a deactivated surface-bonded sol-gel coating on a surface of the tube structure to form a stationary phase coating on that surface of the tube structure. According to the present invention the deactivated stationary phase sol-gel coating enables separation of analytes while minimizing adsorption of analytes on the separation column structure.

Abstract: An etch chamber and a method of reducing back flow of particles in an etch chamber having a valve connected thereto. The etch chamber comprises a valve connected to the etch chamber; and a liner a liner disposed to cover an internal gap between a flange portion of the valve and a flange portion of the etch chamber.

Abstract: The subject invention concerns zirconia-based hybrid organic-inorganic sol-gel coating for optional use as a stationary phase in capillary microextraction (CME), gas chromatographic (GC), high performance liquid chromatography (HPLC), capillary electrophoresis (CE), capillary electrochromatography (CEC) and related analytical techniques. Sol-gel chemistry is employed to chemically bind a hydroxy-terminated silicone polymer (polydimethyldiphenylsiloxane, PDMDPS) to a sol-gel zirconia network. In one embodiment, a fused silica capillary is filled with a properly designed sol solution to allow for the sol-gel reactions to take place within the capillary. In the course of this process, a layer of the evolving hybrid organic-inorganic sol-gel polymer becomes chemically bonded to the silanol groups on the inner capillary walls.

Abstract: A capillary column (10) includes a tube structure having inner walls (14) and a sol-gel substrate (16) coated on a portion of inner walls (14) to form a stationary phase coating (18) on inner walls (14). The sol solution used to prepare the sol-gel substrate (16) has at least one baseline stabilizing reagent and at least one surface deactivation reagent resulting in the sol-gel substrate (16) having at least one baseling stabilizing reagent residual and at least one surface deactivating reagent residual. A method of making the sol-gel solution is by mixing suitable sol-gel prescursors to form the solution, stabilizing the solution by adding at least one baseline stabilization reagent, deactivating the solution by adding at least one surface deactivation reagent to the solution, and reacting the solution in the presence of at least one catalyst.

Abstract: A method of pre-concentrating trace analytes is accomplished by extracting polar and non-polar analytes through a sol-gel coating. The sol-gel coating is either disposed on the inner surface of a capillary tube or disposed within the tube as a monolithic bed.

Abstract: The present invention provides for a column for use in capillary electrochromatography including a tube, wherein the tube includes an inner surface having a positively or negatively charged, chemically-bonded stationary coating thereon. The present invention further provides for a method of making a column for use in capillary electrochromatography, including a tube, wherein the tube includes an inner surface having a positively or negatively charged chemically-bonded stationary coating thereon, wherein the steps include filling the column with a sol-gel solution, maintaining the sol-gel solution within the column, and forcing the sol-gel solution out of the column with an inert gas. Further, the present invention provides for a method of analytical separation with a column including an inner layer having a positively charged chemically-bonded stationary coating thereon that reverses the direction of electroosmotic flow in the column compared with a column without the positive surface charge.

Abstract: A sol-gel poly-THF coating was developed for high-performance capillary microextraction to facilitate ultra-trace analysis of polar and nonpolar organic compounds. Parts per quadrillion level detection limits were achieved using Poly-THF coated microextraction capillaries in conjunction with GC-FID. Sol-gel Poly-THF coatings showed extraordinarily high sorption efficiency for both polar and nonpolar compounds, and proved to be highly effective in providing simultaneous extraction of nonpolar, moderately polar, and highly polar analytes from aqueous media. Sol-gel poly-THF coated microextraction capillaries showed excellent thermal and solvent stability, making them very suitable for hyphenation with both gas-phase and liquid-phase separation techniques, including GC, HPLC, and CEC.

Abstract: A method is presented describing in situ preparation of the titania-based sol-gel PDMS coating and its immobilization on the inner surface of a fused silica microextraction capillary. Sol-gel titania-poly (dimethylsiloxane) (TiO2-PDMS) coating was developed for capillary microextraction (CME) to perform on-line preconcentration and HPLC analysis of trace impurities in aqueous samples. The sol-gel titania-based coatings demonstrated strong pH stability and enhanced extraction capability over other commercially availble GC coatings. Extraction characteristics of a sol-gel titania-PDMS capillary remained practically unchanged after continuous rinsing with a 0.1 M NaOH solution (pH=13) for 12 hours.

Abstract: The present invention provides for a capillary column including a tube structure having an inner surface and a sol-gel substrate bonded to a dendrimer substrate to form a sol-gel dendrimer matrix that bonds to a portion of the inner surface of the tube structure to form a surface-bonded stationary phase coating thereon. The present invention additionally provides for a capillary column including a tube structure having an inner surface, a stationary phase coating attached to a portion of the inner surface, and a dendrimer moiety bonded to the stationary phase coating. Further, a sol-gel dendrimer coated apparatus including a structure having a surface and a sol-gel substrate bonded to a dendrimer substrate to form a sol-gel dendrimer matrix coating the surface thereon is provided. The present invention also provides for a one-step method for making and preparing a column and a method of making the sol-gel and dendrimer solution.

Abstract: A method of preconcentrating trace analytes is accomplished by extracting polar and non-polar analytes through a sol-gel coating. The sol-gel coating is either disposed on the inner surface of a capillary tube or disposed within the tube as a monolithic bed.

Abstract: A capillary column (10) includes a tube structure having inner walls (14) and a sol-gel substrate (16) coated on a portion of inner walls (14) to form a stationary phase coating (18) on inner walls (14). The sol solution used to prepare the sol-gel substrate (16) has at least one baseline stabilizing reagent and at least one surface deactivation reagent resulting in the sol-gel substrate (16) having at least one baseline stabilizing reagent residual and at least one surface deactivating reagent residual. A method of making the sol-gel solution is by mixing suitable sol-gel precursors to form the solution, stablizing the solution by adding at least one baseline stabilization reagent, deactivating the solution by adding at least one surface deactivation reagent to the solution, and reacting the solution in the presence of at least one catalyst.

Abstract: A solid phase microextraction (SPME) fiber including a fiber and a deactivated surface-bonded sol-gel coating on a portion of the fiber to form a solid phase microextraction coating on the portion of the fiber, wherein the solid-phase microextraction coating is capable of preconcentrating trace organic compounds in various matrices. A sol-gel method of preparing SPME fibers with chemically bonded stationary phase coatings that serve as solvent-free extraction media including the step of chemically bonding the sol-gel stationary phase with the SPME fiber surface during its creation through sol-gel reactions.

Abstract: A method of preparing a sol-gel monolithic column includes the step of forming a separation bed (14) from a sol-gel solution in a single process step. This column has improved characteristics for CEC based on its incorporated surface charge and ease of operation due to a lack of or need for end frits. Also, a second type of column includes an optical window (30) for on-column detection.

Abstract: The present invention provides for a column for use in capillary electrochromatography including a tube, wherein the tube includes an inner surface having a positively or negatively charged, chemically-bonded stationary coating thereon. The present invention further provides for a method of making a column for use in capillary electrochromatography, including a tube, wherein the tube includes an inner surface having a positively or negatively charged chemically-bonded stationary coating thereon, wherein the steps include filling the column with a sol-gel solution, maintaining the sol-gel solution within the column, and forcing the sol-gel solution out of the column with an inert gas. Further, the present invention provides for a method of analytical separation with a column including an inner layer having a positively charged chemically-bonded stationary coating thereon that reverses the direction of electroosmotic flow in the column compared with a column without the positive surface charge.

Abstract: A method of preconcentrating trace analytes is accomplished by extracting polar and non-polar analytes through a sol-gel coating. The sol-gel coating is either disposed on the inner surface of a capillary tube or disposed within the tube as a monolithic bed.