The filtration of the samples generated during the dissolution testing is absolutely necessary before the analytical tests. When performing manual dissolution testing, the filtration is carried out manually in most of the cases through a cannula filter and/or a syringe filter. When performing automatic dissolution, the filter of 1-70 µm pore size at the end of the sample probe is used for the single filtration of the samples, however, for liquid chromatographic tests, filtration through 0.22 µm pore size filters may be required. The latter one can be carried out with syringe filters placed in the liquid path. With these filters the Hanson G2 syringe pump samplers are capable of filtering the samples in both push-through and pull-through modes from the undissolved particles. However, in the case of multi-point sampling it may occur that the filter clogs and must be replaced during the examination. The automatization of the syringe filter change is possible with the AutoFilter Changer manufactured by the Hanson Research.
The AutoFilter module filters the samples taken during the dissolution sampling through syringe filters of 25 mm diameter. The module does not require individual filters, only compatible ones with this instrument. Automatic compatible and manual filters of 0.22 – 5.0 µm with luer connector can be used. The diameter of the filter cannot exceed 30.2 mm and the thickness of the filter body is not more than 6.6 mm. The AutoFilter is capable of accommodating 8 x 25 filters. It is equipped with a color touch screen, usual for the other Hanson modules, the internal memory of it is 100 programs and it is suitable for storing 50 users. The compatible internal software of the 21CFR11 provides password protection. Connected to the Hanson G2 automatic dissolution system, the complete control of the instrument is carried out by the sampler.
Configured from the software:
- number of filter positions (6, 7 or 8)
- sampling without filtering
- rinsing without filter
- the volume of the rinsing solution flowing through the filter
- number samplings on one filter
- push-through and pull-through mode module configuration
The instrument has been designed for filter saving operations; therefore, the multiple use of the filters is possible. The time of the filter replacement during the dissolution is programmable, not only after each sampling is possible to be done. At the design of the AutoFilter it was also important that the long-term dissolutions should be accomplished without fewer interruptions.
The filters placed in the metal-free liquid path are perceived individually, therefore, the instrument is able to carry out the sampling even if problems occur. In such cases the sampling without filtering will not be interrupted, the instrument will try to insert the filters again at the next sampling. However, if it happens that the AutoFilter stops for any reason during the operation, the liquid paths visible for the user provide quick and easy troubleshooting. For tests which do not require filtering through syringe filters, do not need remounting or the use of blind filters, the program must be set to avoid the use of syringe filters.
The dimensions of the instrument are: 49x44x68 cm, 29 kg.