BASF Fine Chemicals Generic Drug Formulations 1998
physical properties of the active sub- stance. This particularly concerns the
particle size.
Fig. 3 shows the difference that can occur when ascorbic acid tablets of
the same composition are produced at the same pressure, but when the
active substance consists of crystals of two different sizes crystalline =
150 µm; powder = 150 µm.
2.6 Effect of the physical properties of the excipients
Characterization of the physical pro- perties of excipients is also important.
This is demonstrated in Table 2 in the light of the example of hydrochloro-
thiazide. Tablets of greater hardness are obtained if fine instead of coarse
Povidone K 90 is taken. To a certain extent, the disintegration and the
release are also affected.
2.7 M ethods of measuring the properties of tablets
The general instructions for the deter- mination of the corresponding pro-
perties of tablets are contained in the Pharmacopoeiae Ph.Eur. or USP. If it
is not stated to the contrary, the disintegration time is measured in
artificial gastric juice. The release is determined by the methods laid down
in the corresponding monographs for the tablets usually USP and in the
prescribed medium.
2.8 Information on dissolution of active substance
Nowadays it is standard practice and or laid down that the in-vitro release
of active substance be checked. Unfortunately, these data cannot be
given for all formulations. This is par- ticularly the case when the active
substance is sufficiently soluble or when the formulation was developed
Table 2 Influence of the particle size of Povidone K 90 on the properties of
hydrochlorothiazide tablets solvent granulation
Formulation I
Hydrochlorothiazide ............... 50.0 mg Povidone K 90 ......................... 7.5 mg
Lactose monohydrate ........... 422.5 mg II
Water .................................... 37.5 mg III
Magnesium stearate ................. 2.5 mg
Tablet properties
Binder Hardness
Disintegration time Dissolution 30 min
Povidone K 90 95 250 µm
66 N 18 min
23 Povidone K 90
15 250 µm 97 N
22 min 19
BASF Fine Chemicals Generic Drug Formulations 1998
in a time when this parameter was not yet demanded.
2.9 Formulations
The formulations in this chapter have been arranged in the alphabetic order
of their active substances.
3 Coating of tablets and
capsules
3.1 Size of formulations and amounts used
The formulations were developed on a laboratory scale.
The batches usually consisted of ca. 1 kg of spray solution or spray sus-
pension and 5 kg of tablet cores.
3.2 Equipment
The tests were mostly performed in the Accela-Cota 241, for which the
minimum amount of cores is 5 kg. In a few cases, the fluidized-bed granu-
lator WSG Glatt 15 or a traditional coating pan was used.
3.3 Conditions for spraying
Whenever they are of importance, the conditions for processing the formula-
tions on a given scale have been quo- ted.
3.4 Colour additives
Normally the colorants added were Sicovit colour lakes or Sicovit pig-
ments. To a certain extent, these two are interchangeable.
3.5 Formulations
The formulations in this chapter have been arranged in the alphabetic order
of their function.
BASF Fine Chemicals Generic Drug Formulations 1998
4 Granules, powders, dry
syrups and lyophilisates
4.1 Size of formulations and amounts used
