The future of research tabletting equipment

Bruno Villa, general manager at MedelPharm discusses what lies in store for the future of research tabletting equipment.

In the last 15 years the offer of research tabletting equipment has evolved at an increasing pace, catching up with the evolution of production presses.

Reaching all the desired goals of formulation scientists on a research press had previously been impossible until the beginning of the century.

The technical constraint implied a trade-off in order to get strong and accurate data like force|displacement|die wall pressure out of a small sample at a high compression speed and in a clean and easy manner.

Historically research equipment has been evolving around slow single-punch equipment, “eccentric presses”, which are easy to instrument and well adapted to early stage. This is the oldest and is still a frequently used solution you will encounter in every laboratory and university in the world. The most famous being the Korsch EK0/XP1 family which have been heavily copied around the world. With a single punch, this type of equipment can produce tablets suitable for consumption. The compression event being relatively slow ensures good tablet cohesion, hiding potential issues appearing at high speed.

As development was advancing, formulation scientists were then moving to a downsized rotary press (8-10 punches), if enough powder was available, usually after several years of process. They were trading speed of compression for accuracy of data acquisition. In that trade-off, the speed sensitivity information is invaluable and so is measuring the benefits of pre-compression on tablet quality. In addition, small rotary presses can produce small to medium size batches fairly rapidly using similar punches than production, but not with a tablet quality comparable to large scale production speed. The most famous being the RIVA Piccola and Korsch XL100.

Both these machines can create tablets fitted for consumption and despite their limitations, these technologies represent the largest share of R&D tablet press market in volume. In both cases copies and exotic sourcing provides equipment for the most cost conscious customer with various success.

Alternatively, scientists and academic researcher went one step further trading ease of use and GMP practices against an even higher speed of compression and a very consequent budget with hydraulic-actuated equipment. Still, these solutions were not satisfactory, and some companies tried to fill the gap with interesting concepts with various new benefits but also new trade-offs. Some laboratory and academics went with custom-made concepts designed to fit their needs but not always easy to maintain in the long run.

The appearance of standard easy to use, mechanical equipment combining ease of use, quality of instrumentation, high speed tabletting, and small batch production has convinced the scientists of this new approach at an affordable budget. The STYL’One Evolution has fulfilled this vision with an even more complete offer, of instrumentation for research, of accessories for production and flexibility for marketing creativity.

Research scientists enjoy high precision measurement with scalable sensitivity for multilayer tamping, different force feeding system for the most difficult flowing powder, production rotary press simulation as well as dry granulation/roll compaction simulation for ensuring robustness of formulation.

The same equipment is used with production in mind including external lubrication capacity or weight regulation with tablet rejection. These batches of 10 or 20,000 tablets per day are real prototypes of a press running at 400,000 tablets per hour - bearing in mind that 50 punches produce 50 times more than a single one! However, these batches are useful in orphan drugs production or oncology with full containment application.

Using a similar concept and based on the technology of “Electro mechanical actuated equipment”, we now see a new generation of more affordable, benchtop equipment answering the needs of USP 1062 requirements and replacing both the historical single punch eccentric press and small rotary research press efficiently. Being even more affordable and easier to handle, this equipment can be expected to rapidly replace the classic solutions in quality-driven formulation laboratories. The only limitations are the production capacity of a single punch press and medium speed of compression.

What do we have to expect in the near future? This niche market of research tabletting instruments is evolving fast, pushed by innovation and competition. We expect new players entering that segment now that the demand for these new technologies has been created and acknowledged. Meeting the stringent requirements is still a challenge to be overcome.

We also see growing interest for purely mathematical models (DEM/FEM). Computers following “Moore’s’s law” will offer even more calculation capacity for these models making them more detailed and available to a larger group of scientists.  At one point in time, however, we will be back to square one: powder has to be put into a die to make tablets to confirm the mathematical model.