The disintegration test
To demonstrate the disintegration time required for tablets containing Parteck ODT, two drug formulations (Table 1) with different grades of ascorbic acid as the active were compared.
Table 1: Ingredients for Formulations 1 and 2 used to test tablet disintegration time.
Parteck ODT, ascorbic acid and Evogran orange flavour were blended together for 5 min in a Turbula (Glen Mills Inc., NJ, USA)
shaker-mixer. Afterwards, sucralose granular (Merck KGaA) and Parteck LUB MST magnesium stearate were sieved through a 250-μm
sieve onto the mixture, and then all components were again blended for 5 min. The tabletting mixture was then compressed on
a Korsch EK 0 single punch instrumented tablet press (Korsch AG, Berlin, Germany [52 rpm, 11 mm diameter punch, biconvex])
into tablets each weighing 400 mg.
The drug release test
To show the drug release kinetics in vitro, two Parteck ODT drug formulations (Table 2) with acetaminophen of different grades and provenience as active substance were assessed. For each formulation, Parteck
ODT, acetaminophen and silicon dioxide highly dispersed were blended for 5 min and passed through a 1.0-mm sieve. Lubricant
(Dynasan 118 micro fine for Formulation A and PRUV sodium stearyl fumarate for Formulation B) was then sieved through a 250-μm
sieve onto the mixture and then all components again blended for 5 min in a Turbula shaker-mixer. The tabletting mixtures
were then compressed on a Korsch EK 0 single punch instrumented tablet press into 500 mg tablets.
Table 2: Ingredients for Formulations A and B used to test drug release kinetics.
What do the results say?
Good compression, low wear and tear
Using a scanning electron microscope (SEM), the morphology of the Parteck ODT formulation appeared very rough and structured.
This microstructure leads to good compression behaviour and means that high tablet strength is achievable with low compaction
forces. This structure is also ideal for minimizing wear of the tabletting equipment or to introduce high amounts of active;
up to 50% active can be directly compressed with Parteck ODT — usually the content of active in direct compression is limited
to about 20–30% (Table 3 and Figure 1).
Table 3: Physical data for acetaminophen tablets based on Parteck ODT.
Experience with this type of polyol excipient usually shows a great deal of wear of the granulated particles upon mechanical
stress. Thus, one would expect that the needle-like structure of the Parteck ODT material, as seen on the SEM, would be crushed
during compression. The morphology, however, surprisingly remains unchanged after mixing and compression. This contributes
to a very large specific surface area of the tablet matrix of up to 3.5 m2/g. Such an exceptionally large surface area can bind small API particles well and prevent de-mixing. In addition, this enhances
the water uptake and dissolution of the tablet matrix. So it is not only the superdisintegrant that is responsible for fast
dissolution of the overall product; the unique surface structure of the binder contributes too.
Figure 1: Compression profiles for ascorbic acid tablets based on Parteck ODT with 80 mg ascorbic acid, 1% magnesium stearate,
0.5% orange flavour and 0.2% sucralose.