DSR-M
The dissolution sampling robot with media refilling and dilution option.
DSR-M
Dissolution Sampling Robot
The DSR-M dissolution sampling robot is designed specifically for the sample transfer and sample processing from a six to twelve vessel dissolution bath. This unique versatile instrument allows samples to be collected over very short time intervals. The DSR-M can be equipped to collect, dilute or process samples for following UV-Visible or HPLC measurements. It can also be used for dissolution medium replenishment to conform to USP/EP volume loss rules.
Automated Sampling
To offer the highest volume precision, between six and thirteen piston pumps are used for sample removal and media refilling (optional), one dedicated pump for each channel. No time consuming pump calibration is needed. The advanced design of the system means that it is always ready for operation. The pumps are integrated into the DSR-M as a compact CAT-M pump module. The sample preparation station, Z-arm and needle, can be used to dispense into septa sealed HPLC vials or dilute the samples for later UV/VIS analysis. Keeping the samples in sealed vials helps to avoid evaporation, especially if sustained release samples are tested.
The DSR-M can be connected to a Pharma Test PTWS-series and PT-DT70 dissolution bath. If the DSR-M is connected to a PTWS 820D, PTWS 620, PTWS 1220, PTWS D620 or PTWS 1420 dissolution bath the sampling probes are connected to its EPE auto sampling manifold. The motorized EPE lowers the sampling probes into the corresponding sampling position which can be set for either 500 or 900ml total media volume. Sampling cycle information is programmed directly at the dissolution bath using the method filing system.

Sampling Racks
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 analyzed over prolonged time periods. The Pharma Test DSR-M provides a neat solution for this automation procedure. Up to 20 sampling cycles can be run (10 if dilution is enabled). These are collected in two racks inside the DSR-M. The second rack is used either for sample collection or for sample processing, such as dilution. The unique rack design allows the user to use standard open vials or septa closed HPLC vials with the same rack.
Filtration and MFC-12
Filtration of the collected samples can be done using 5 to 20 micron filter tips which are attached to the sampling probes and also using the MFC-12 manual filter changer which is integrated into the DSR-M tubing and may hold round filters from 1 to 0.45 micron. Since these round filters pass liquid in one direction only, an additional DSR-MVS valve station is required to create a bypass for the return flow.
Dilution of Sampled Media
If dilution of sampled media is required the DSR-M will use one of the two racks to collect the samples from the dissolution vessels and the second one will hold empty vials into which the diluted media will be dispensed. When sampling is finished the DSR-M will start to dilute. It will take the volume which needs to be diluted from the sampled media dispense it into the empty vials and add the diluent while mixing both using air.
All vials are treated the same time in either open or septa-sealed vials. The DSR-M racks are installed on a tray that can be moved out of the DSR-M easily to transfer the vials and to fill up the rack with new empty vials or glass tubes. The DSR-M is completely enclosed by transparent acrylic glass to protect the operator from the moving arm and the samples from any external source.
Technical Data of the Dilutor Pump
ParameterSpecification
Pump Head Volume | 100µl |
Dispensing Volume | 5µl – 250ml or continuous dispensing |
Flow Rate | 0.1 – 20 ml/min. +/- 1% (related to pump head volume) |
Coefficient of Variation CV | Using additional piston pumps (CAT-RM module, optional) |
Interface | RS485 / RS232 for User Calibration |
Pump Head Materials | Al2O3, PVDF |
We reserve the right to make technical changes without any prior notice.

The Piston Pumps
Unlike most systems the DSR-M does not use syringes but valve-less piston pumps. These pumps do not need any time consuming pre-filling and emptying cycles and change of valve positions. Also the dead volume is much smaller compared to conventional syringes and valve installations. A rinsing valve is connected to each sampling and refilling valve to clean them using fresh diluent or media to avoid clocking due to the recipients inside the collected media. Fast coupling systems allow the change of each individual pump head whenever this should become necessary. There are no wear and tear parts inside the pumps needing to be replaced; the precision is kept for the total life time.
Features
- Features valve free piston pumps for high precision
- Modular design to allow auto media refill, dilution and transfer into sealed vials for six to twelve station dissolution baths
- Up to 20 sampling cycles (10 cycles with dilution)
- Less than 1% transfer error
- Supports 0.45 micron filtration using MFC-12 manual filter changer and DSR-MVS valve station
- Sampling sequences are programmed direcly at the Pharma Test dissolution bath
- Stand-alone mode available to support third party dissolution baths
Technical Specifications
Number of sampling cycles | Up to 20 samples from a maximum of 13 vessels |
Sampling volume | 0.1 ml to 25.5ml |
Accuracy | < 1% transfer error |
Flow rate | Minimum 1 ml/min.; Maximum 41 ml/min. |
Media refilling | Using piston pumps (CAT-MRM module, optional) |
Sample processing | X-Y-Z arm with septum piercing needle (optional) |
Dilution factor | Maximum 1:100 |
Display | Backlit LCD |
Data entry | Function keys |
Materials used | All wet parts: 99.7% Al2O3, Teflon or PEEK |
Tubing | 1.0mm ID to 1.6mm OD FEP or PTFE (not included in supply scope) |
Dispensing probe positioning | ± 0.8mm |
Sample processing probe | ± 0.5mm |
Repeatability | ± 0.3mm |
Interface | RS232 port, analogue signal I/O port |
Power | 110/230 Volt, 50/60 Hz |
Instrument dimensions | Approx. 45cm x 55cm x 53cm (width x depth x height) |
Packaging dimensions | Approx. 80cm x 120cm x 75cm (width x depth x height) |
Net weight | Approx. 49kg |
Gross weight | Approx. 64kg |
Certification | All components certified to USP / EP requirements |
CE / EMC certification | All CE / EMC Certification provided |
Validation | All IQ & OQ documents included |
We reserve the right to make technical changes without any prior notice.
Options
- CAT-DM dilution and sample transfer module
- MFC-12 manual filter changer
- DSR-MVS valve station