Pharma Test

IDS1000
Fibre Optic Dissolution Testing In-Situ Dissolution Test System

The IDS 1000 in-situ dissolution system with fibre optic technology brings direct measurement technology to dissolution testing. Sample measurement is automated and self-contained, there is no need for samples to be pumped out of the dissolution vessels at all. The IDS 1000 includes an automated tablet drop magazine for the synchronous release of up to eight samples. The built-in vessel covers close the dissolution vessel completely, reducing evaporation to a minimum. The vessels are arranged in a 4 + 4 configuration, stirring speed, temperature and stirrer immersion position can be set using the WinDiss ARGUS software.

The in-situ measurement is performed by fibre optic probes which are located in the centre of the stirring shafts of the dissolution tools, i.e. paddle or basket (USP App. 2 or 1). The probe can be removed from the shaft so that various path length inserts can be employed for different active concentrations and extinction coefficient ranges. In-situ probe placement means fast measurement times and no need for sample transportation. Fast change-over times are another advantage, since no flushing of tubing or flow cells is required. If the solution becomes turbid, algorithms, which analyse the whole spectrum and eliminate signal interference due to scattered light from non-soluble excipients floating in the medium, can be employed. Only the signal obtained from adsorbed light is measured and recorded.

The IDS 1000 also differs from other fibre optic dissolution systems, as it has only one built-in diode array spectrophotometer, but is still able to operate with up to 8 separate fibre optic sensor paths which are multiplexed to a central sampling unit. The fibres are only illuminated with UV light when required to make a measurement, thus prolonging the fibre sensors’ operational life. The biggest difference is that all IDS 1000 components, including the built-in UV or UV/VIS diode array spectrophotometer are contained in a single dissolution testing instrument housing, so that all optical components have a fixed geometry. The built in diode array spectrophotometer eliminates restriction to single wavelength measurements and can accumulate whole spectra, optimising the analytical wavelength used. This allows the use of first derivative techniques in order to analyse multi-component formulations with overlapping absorption curves.