Methods and kits using a humidifying agent to prevent or reduce aging of a silica-based columns. A beneficial result of the method is associated robustness of column nucleic acid binding capacity, compared to an aged column.

Methods and kits using a humidifying agent to prevent or reduce aging of a silica-based columns. A beneficial result of the method is associated robustness of column nucleic acid binding capacity, compared to an aged column.

Disclosed is a method for the determination of impurities in polyalkylene ethers and polyalkylene amines comprising the steps i) introducing polyalkylene ethers or polyalkylene amines as an analyte into a chromatography column containing monolithic silica gel as a stationary phase, ii) eluting the analyte with a liquid elution agent having such a polarity that the analyte is in adsorptive equilibrium with the stationary phase during chromatography, iii) detecting the components of the analyte at the exit-side end of the chromatography column, receiving a chromatogram, which shows different components of the analyte and its qualitative amount depending on the elution time of the individual components, and iv) identifying bands in the chromatogram having a low height or area compared to the band with the largest height or area as an indication of the presence of impurities in the analyte.

The method allows in an easy manner to identify impurities in the sample. The method can be used for quality control but also for the preparative cleaning of the sample.

Superficially porous particles are disclosed, each including a solid core and a layered porous shell. The layered porous shell includes a porous inner layer and at least one porous outer layer, a shell skeleton thickness greater than 1 nm, and constitutes from 10 vol % to 90 vol % of the plurality of superficially porous particles. The porous inner layer includes an inner layer thickness of less than 300 nm. The at least one porous outer layer includes a cumulative outer layer thickness ranging from 1 to 100 times the inner layer thickness, a predominately radial pore orientation, and an outer layer pore structure which is more organized than the inner layer pore structure. A layer-by-layer process for forming a plurality of superficially porous particles with layered structure is disclosed. A post-modification process for preparing a plurality of chromatographically enhanced superficially porous properties is also disclosed.

Superficially porous particles are disclosed, each including a solid core and a layered porous shell. The layered porous shell includes a porous inner layer and at least one porous outer layer, a shell skeleton thickness greater than 1 nm, and constitutes from 10 vol % to 90 vol % of the plurality of superficially porous particles. The porous inner layer includes an inner layer thickness of less than 300 nm. The at least one porous outer layer includes a cumulative outer layer thickness ranging from 1 to 100 times the inner layer thickness, a predominately radial pore orientation, and an outer layer pore structure which is more organized than the inner layer pore structure. A layer-by-layer process for forming a plurality of superficially porous particles with layered structure is disclosed. A post-modification process for preparing a plurality of chromatographically enhanced superficially porous properties is also disclosed.

A chromatography column has a retaining plug permanently fixed to an upstream end of the column and blocks one end of the bore through the column. The plug has a fluid passage therethrough. An upstream end of the passage is preferably but optionally larger in diameter than a downstream end of the passage. An upstream porous member upstream of the retaining plug is held by an upstream end cap and urged toward the plug. Chromatographic media extends from the upstream porous member, through the passage in the retaining plug, to a downstream porous member held by a downstream end cap. The media between the retaining plug and the downstream porous member are under compression to form a bed of packed media.

A chromatography column has a retaining plug permanently fixed to an upstream end of the column and blocks one end of the bore through the column. The plug has a fluid passage therethrough. An upstream end of the passage is preferably but optionally larger in diameter than a downstream end of the passage. An upstream porous member upstream of the retaining plug is held by an upstream end cap and urged toward the plug. Chromatographic media extends from the upstream porous member, through the passage in the retaining plug, to a downstream porous member held by a downstream end cap. The media between the retaining plug and the downstream porous member are under compression to form a bed of packed media.

A method for solid-phase extraction is disclosed. The method includes fabricating a solid-phase extraction medium by incorporating a plurality of modified mesoporous silica particles within pores of a cotton fabric matrix, putting the solid-phase extraction medium in contact with a fluid containing metal ions including one of immersing the solid-phase extraction medium in the fluid containing metal ions or passing the fluid containing metal ions through the solid-phase extraction medium by continuously circulating the fluid through the solid-phase extraction medium, and extracting the metal ions from the fluid by adsorbing the metal ions onto the solid-phase extraction medium responsive to a contact between the solid-phase extraction medium and the fluid containing metal ions.

A method for solid-phase extraction is disclosed. The method includes fabricating a solid-phase extraction medium by incorporating a plurality of modified mesoporous silica particles within pores of a cotton fabric matrix, putting the solid-phase extraction medium in contact with a fluid containing metal ions including one of immersing the solid-phase extraction medium in the fluid containing metal ions or passing the fluid containing metal ions through the solid-phase extraction medium by continuously circulating the fluid through the solid-phase extraction medium, and extracting the metal ions from the fluid by adsorbing the metal ions onto the solid-phase extraction medium responsive to a contact between the solid-phase extraction medium and the fluid containing metal ions.

Provided is a supercritical fluid chromatography method, system, and components comprising such a system wherein a non-polar solvent may replace a portion or all of a polar solvent for the purpose of separating or extracting desired sample molecules from a combined sample/solvent stream. The method and system are designed to eliminate or reduce the amount of polar solvent necessary for chromatographic separation and/or extraction of desired samples to less than or equal to twenty percent polar solvent within the total volume concentration of the total solvents used, and the technique may include one or more of a supercritical fluid chiller, a supercritical fluid pressure-equalizing vessel, and a supercritical fluid cyclonic separator. The supercritical fluid chiller and the use of the chiller allow efficient and consistent pumping of liquid-phase gases employing off-the-shelf HPLC pumps in the supercritical chromatography system using liquid-phase gas mobile phase. The pressure equalizing vessel allows the use of off the shelf HPLC column cartridges in the supercritical chromatography system. The cyclonic separator efficiently and effectively allows for separation of sample molecules from a liquid phase or gas phase stream of a supercritical fluid. The technique may further incorporate the use of one or more disposable cartridges containing silica gel or other suitable medium for use as a chromatographic separation column. The technique may also utilize an open loop cooling circuit using fluids with a positive Joule-Thompson coefficient.