Manual sampling from a dissolution test instrument is not only time consuming but also limits the reproducibility and is close to impossible if sustained release products have to be analysed over prolonged time periods. The Pharma Test DSR (Dissolution Sampling Robot) provides a neat solution to this automation procedure.
To offer the highest volume precision, between 6 and 8 Piston Pumps are used for sample removal and media refilling (if required). No time consuming pump calibration is needed. The advanced design of the system means that it is always ready for operation and as the pump is already built-in the system saves a lot of bench space.
The sample preparation station, Z-arm and needle, can be used to dispense into sealed vials or dilute and/or inject into a single cell Spectrophotometer. Keeping the samples in sealed vials helps avoid evaporation, specially if sustained release samples are tested.
The DSR is connected to a Pharma Test PTWS series Dissolution Bath. Usually the sampling probes are connected to the EPE Auto Sampling Manifold which is available for the following instruments: PTWS 610, PTWS 1210 or PTWS 310. The motorized EPE lowers the sample probes into the corresponding sampling position which is pre-set for either 500 or 900 ml total media volume. A trigger signal starts the DSR sampling pumps so that the preset volume is withdrawn and dispensed into the vials or tubes which are in the sample rack holder. Only one sample line is required from the dissolution tester via the sampling manifold as all liquid sampling and refilling is made through the same tubing. So no need for extra return tubing for refilling and automated tube flushing previous to the consequent sampling interval.
If the DSR is connected to a PTWS 610, PTWS 1210, PTWS 310, PT-DT8 sampling information is entered via the keyboard inside the Dissolution Bath. Sample handling information, such as Dilution Factor, Sample Transfer into empty septa closed vials is programmed at the keypad of the DSR.