Structure-activity relationships of a novel group of large-conductance Ca(2+)-activated K(+) (BK) channel modulators: the GoSlo-SR family.

Opening up ion channels: We synthesised a series of anthraquinone analogues, called the GoSlo-SR family. Their effects on bladder smooth muscle BK channels were examined and, as shown, shifted voltage dependent activation >-100 mV (at 10 μM). They were more efficacious than NS11021 and could provide a new scaffold for the design of efficacious BK openers.

Headspace SPME method development for the analysis of volatile polar residual solvents by GC-MS.

A solid-phase microextraction (SPME) method has been developed and optimized for the polar residual solvent determination in pharmaceutical products. Five different polymer-coated fibers were investigated and the Carboxen/polydimethylsiloxane was found to be the most sensitive for all components. Two Headspace SPME methods were developed and optimized: one for the extraction from aqueous solutions, and the other for the extraction from organic solutions (N,N-dimethyl formamide (DMF) and dimethyl sulfoxide (DMSO).

[Headspace solid phase micro-extraction method optimization for residual solvent analysis].

A systematic headspace SPME method optimization is described for the residual solvent analysis using a polidimethyl-siloxane/divinylbenzene (PDMS/DVB) fiber. The first step was the chromatographic system optimization in which a narrow bore capillary column with a thick film (1 micron) of stationary phase, low starting column temperature (30 degrees C) and a narrow bore injector liner (2 mm I.D.

Residual solvents determination in pharmaceutical products by GC-HS and GC-MS-SPME.

Solid-phase microextraction (SPME) has been applied to the residual solvents determination in pharmaceutical products and was compared with the static headspace. Three fibers with different polymer films were compared and the polydimethylsiloxane/divinylbenzene coated fiber was found to be the most sensitive for the analyzed analytes. Between the investigated sample preparation techniques, gastight-SPME proved to be the most sensitive, with DL values ranging from 5 pg ml(-1) to 2 ng ml(-1).