Could you tell us more about the TSAR project, for which you are collaborating with the University of Nottingham?
Since the launch of our PharmaCote range of punch and die coatings more than five years ago, I Holland has been increasingly
called on to solve sticking issues within the pharmaceutical sector as tablet manufacturers realize that these problems can
be eliminated without reducing product yield and investing in expensive magnesium stearate systems. The traditional way of
troubleshooting a sticking problem would have been to supply a customer with a test set of tools containing many different
punch and die coatings. A full compression trial would be carried out at the customer's site to ascertain the coating that
would most effectively solve the sticking problem. This approach involves a significant investment for the customer in the
tooling as well as in time.
The aim of the TSAR project is to develop a predictive tool that will allow us to identify which punch and die coating is
most likely to solve these sticking issues, thus removing the need to carry out full-scale compression trials with all of
the anti-stick coatings. The development of the predictive tool will not commence until we have gathered sufficient interaction
data from many different excipients and active ingredients. This work is currently in progress as we are testing several samples
supplied by our customers.
We aim to use newly developed multivariant analysis techniques linked to nanoscale surface chemistry and morphology techniques
such as atomic force microscopy (AFM), time-of-flight secondary ion mass spectroscopy (ToFSIMS), Raman spectroscopy, contact
angle measurements, X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), and laser profilometry. Once
the data are gathered, we will use a principle component analysis tool to allow us to group the different excipients/active
ingredients. Only after this process, will we be able to start the development of the predictive tool.
We are currently halfway through the two-year project and have spent the first year solely gathering data from various products
supplied to us by different customers. The most utilized piece of equipment to date has been the AFM, which allows us to quantitatively
map, at the nanoscale, adhesion on PharmaCote coated tablet punches using single drug/excipient particles. The low adhesion
force measurements (nN) gathered within the AFM indicates the level of Van der Waals forces that are present. We are also
changing the humidity and temperature within the testing environment to gather data on capillary forces that are present.
Only when all the ingredients of the formulation are tested in this analytical way, do we move the formulation into a production
environment and compress tablets using the same PharmaCote coated tooling.
This 'real world' checking allows the results of the analytical testing to be verified in a production environment and gives
the customer the reassurance that they are purchasing the optimum solution for their specific problem. It cannot be stressed
enough how each sticking problem is unique and can vary significantly from site to site, press to press, and product to product,
which makes laboratory compression testing vital.
1. Eurostandard Educational Collection 2010 Edition.
2. T. Higgins, Pharm. Tech.
37 (2) 30–31 (2013).