Use of conventional bioanalytical devices to automate DBS extractions in liquid-handling dispensing tips.

Background: Conventional liquid-handling devices were employed, along with an improved punching device, to semi-automate dried blood spot (DBS) extraction of alprazolam, α-hydroxyalprazolam and midazolam from human whole blood. Liquid-handling devices were used to add internal standard to the DBS cards and to extract the analytes from the DBS, in order to be analyzed by HPLC-MS/MS.

Results: The technique was shown to be accurate (±12.

Development and validation of an HPLC-MS/MS method for the analysis of dexamethasone from pig synovial fluid using dried matrix spotting.

Background: Dried matrix spot techniques were employed to validate an HPLC-MS/MS assay for the determination of dexamethasone in clear Yorkshire pig synovial fluid using 15 µl of sample. We have adopted the term dried matrix spot to indicate that the techniques used for dried blood spots can be applied to nonblood matrices. The dried matrix spot method employs a color-indicating process developed at Alturas Analytics that enhances the ability to analyze transparent fluids spotted onto collection paper by allowing the analyst to visually verify the location of the dried sample spot.

Enhanced reactivity of superoxide in water-solid matrices.

Superoxide is unreactive in deionized water, but aqueous systems containing added solvents, including H2O2 at >100 mM, show significantly increased reactivity of superoxide with oxidized organic compounds such as highly chlorinated aliphatics. The potential for solid surfaces to similarly increase the reactivity of superoxide in water was investigated. Heterogeneous birnessite (gamma-MnO2)-catalyzed decomposition of H2O2 promoted the degradation of the superoxide probe hexachloroethane (HCA) at H202 concentrations as low as 7.

Electrochemical detection of triacetone triperoxide employing the electrocatalytic reaction of iron(II/III)-ethylenediaminetetraacetate and hydrogen peroxide.

An electrochemical method for the detection of triacetone triperoxide (TATP) is proposed and examined. In this method, TATP solutions were treated with 1.08 M HCl for 10min releasing H2O2 and/or hydroperoxides.