The highest degree of automation and flexibility is offered by the new half-automated Dissolution System. The HADs bases on the full validated software of the ERWEKA RoboDis and therefore is prepared for UV-VIS-, HPLC analysis, fraction collection as well a combination of all. That’s the breakthrough for method development as well as for highest flexibility.



The HADs uses an innovative flow-through system of sealed PEEK-vials. The sample is withdrawn from the dissolution vessel through tip filters from 1 µm porosity by a peristaltic pump (in case of filtration from 0.45 µm porosity instead the membrane filter changer AFC 825 (see page 39) or double filtration station in combination with the piston pump PVP 820 can be used) to the PEEK block of sealed flow-through vials integrated in the auto sampler.

Operation
A x/y/z driven arm with an embedded syringe picks up the samples from the flow-through vials and store them into HPLC vials (max. 324 sealed vials; optionally electronically tempered from 4° to 70°). A time managing program optimizes and calculates when a sample can be transferred from the HPLC-Vials to the Rheodyne valve for HPLC analysis. A direct online injection without buffering the samples is also possible.

The auto sampler offers such features as multiple standard racks for HPLC device calibration, needle wash station, replacement of the withdrawn sample volume by fresh media.

HPLC Online connection
Connection to equipment of all manufacturers for e. g. Shimadzu, Agilent and Waters as well as the possibility of a connection to different chromatograph systems like Empower (Waters) or Cerity (Agilent).

UV-VIS Online Connection
In addition to the HPLC connection the ERWEKA HADs offers the possibility to include a UV-VIS Spectrophotometer (ERWEKA, Perkin Elmer, Shimadzu, Analytic Jena, Agilent) into the close-loop sample withdraw system, so i.e. between the sample transfer pump and the PEEK flow-through vial block or the PEEK flow-through vial block and the return to the dissolution tester.

Therefore the ERWEKA HADs can be used as sample collection device (max. 324 samples; incl. sample tempering), a HPLC Online System in combination with virtually any brand of HPLC device and an Online UV-VIS system (incl. virtual dilution by various path length with optimized flow-through cuvettes).

Capacity
The ERWEKA HADs allows two Dissolution testers via two individual sample transfer pumps to one auto sampler with two embedded PEEK flow-through vial blocks (no cross contamination). Either none, one or both of the Dissolution testers, in addition to the HPLC Online system, can be fitted with a UV-VIS Spectrophotometer inside the close-loop sampling system.

Software
Based on the ERWEKA® standard dissolution software, the system enables the im-/export to other IT-systems for e. g. LIMS or chromatography data systems. Also the automatic recording of sampling times, temperature and rotation speed in each vessel brings facilitation. Every deviation is documented automatically.

Video monitoring
An automated system runs without user observation. What to do when the results of the dissolution test aren’t as expected, too low or too high? Nobody had been there during the test, nobody knows if this has been caused by the sample itself or by system errors such as coning, sticking etc. So what to do with the incorrect results? To through them and hide them from the authorities?

To eliminate that problem completely the ERWEKA HADs is available with video monitoring of six dissolution vessels of one or both connected dissolution testers. The video monitoring allows recording of each test-run in combination with real-time overlapping dissolution profile to identify disturbances such as coning etc. and to get the visual impression of 24 hours in 2 minutes. The video monitoring is a very powerful tool for method development as well for troubleshooting.