This invention employs columns and methods to apply external and internal standards and compounds. Analytical standard or compounds are adsorbed to a solid phase extraction media and are stored indefinitely. The standards or compounds remain stable on the solid phase extraction media without decomposing. The standards or compounds may be removed from the solid phase extraction media with a solvent.

An adsorbent bed, including at least one elementary composite structure that includes adsorbent particles in a polymer matrix, wherein the adsorbent bed has a bed packing, .sub.bed, defined as a volume occupied by the at least one elementary composite structure V.sub.ecs divided by a volume of the adsorbent bed V.sub.bed where .sub.bed is greater than 0.60.

An adsorbent bed, including at least one elementary composite structure that includes adsorbent particles in a polymer matrix, wherein the adsorbent bed has a bed packing, .sub.bed, defined as a volume occupied by the at least one elementary composite structure V.sub.ecs divided by a volume of the adsorbent bed V.sub.bed where .sub.bed is greater than 0.60.

An adsorbent bed, including at least one elementary composite structure that includes adsorbent particles in a polymer matrix, wherein the adsorbent bed has a bed packing, .sub.bed, defined as a volume occupied by the at least one elementary composite structure V.sub.ecs divided by a volume of the adsorbent bed V.sub.bed where .sub.bed is greater than 0.60.

A particulate plug for removing a preservative from a solution, suspension, or emulsion comprising a drug is presented. The plug comprises microparticles of oxidized polyolefin (OxPO). The microparticles are irregular-shaped rigid aggregates and are sized and packed to yield a hydraulic permeability greater than 0.01 Da. The OxPO have absorbed portions of a preservative to be removed and/or a drug for delivery in solution, as can the copolymer.

A particulate plug for removing a preservative from a solution, suspension, or emulsion comprising a drug is presented. The plug comprises microparticles of oxidized polyolefin (OxPO). The microparticles are irregular-shaped rigid aggregates and are sized and packed to yield a hydraulic permeability greater than 0.01 Da. The OxPO have absorbed portions of a preservative to be removed and/or a drug for delivery in solution, as can the copolymer.

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.

In embodiments, a packing material for supported liquid extraction has a sorbent media that includes synthetic silica particles. In embodiments, the synthetic silica particles can have physical properties relating to one or more of particle surface area, shape, size, or porosity. In one embodiment, synthetic silica particles have a surface area less than about 30 m.sup.2/g. In another embodiment, the synthetic silica particles have an approximately uniform particle shape. In further examples, synthetic silica particles have a particle size in a range of about 30-150 m inclusive or greater than about 200 m. In another embodiment, synthetic silica particles are arranged to have a pore size greater than about 500 Angstroms. In an embodiment, an apparatus for supported liquid extraction includes a container and a sorbent media that includes synthetic silica particles. In a further embodiment, a method for extracting target analytes through supported liquid extraction is provided.

An activated carbon device for adsorbing solvent from a flow of air is regenerated by feeding heated inert gas to the activated carbon and by applying a reduced pressure to the heated activated carbon.

Disclosed in certain embodiments are sorbents for capturing heavy hydrocarbons via thermal swing adsorption processes.