Solid oral tablets: direct compression II
Writer： admin Time：2020-03-18 17:14 Browse：℃
3.Prescription
Since DC is sensitive to API, non-uniform mixing might occur when LE is low. However, when LE is high, especially when API is of bad fluidity and compressibility, problems will occur in these two aspects. Based on LE, design of DC can be shown in the following picture:
1)Thinner
As it is the auxiliary used most, thinner influences fluidity and compressibility in DC vitally. Besides some regular stable physical and chemical properties, thinner would better obtain pretty good adhesion.
MCC
For API of high LE but bad compressibility, compressibility and dilution of thinner are critical. Dilution of auxiliary material refers to the largest proportion of API in medicine when materials can be compressed into acceptable medicine by thinner. MCC acquires low density, large porosity, high dilution and compressibility. but dilution of sprayed and dried lactose is of poor dilution.
MCC, the only adhesion in DC currently, can provide good compressibility for materials. Its size distribution is pretty large, which enables it to be mixed with auxiliary materials of variable size but avoid stratification. Since it is fibrous, MCC has worse fluidity than sprayed and dried lactose. When humidity is high, MCC obtains certain hygroscopicity, so tablets of much MCC can be softened easily in high humidity. But this process is reversible. MCC used in DC is level PH102.
|
Avicel PH |
101 |
102 |
103 |
113 |
112 |
200 |
301 |
302 |
105 |
|
Particle size distribution (μm) |
50 |
90 |
50 |
50 |
90 |
180 |
50 |
90 |
20 |
|
Tap density (g/cc) |
0.45 |
0.45 |
0.45 |
0.44 |
0.48 |
0.42 |
0.59 |
0.60 |
0.46 |
|
Moisture |
NMT 5.0 |
NMT 5.0 |
NMT 3.0 |
NMT 2.0 |
NMT 1.5 |
NMT 5.0 |
NMT 5.0 |
NMT 5.0 |
NMT 5.0 |
Lactose
SDL is the earliest used to function as filler. It is of good fluidity and compressibility. Its shape of ball makes it become the auxiliary of the best fluidity among all DC thinner. But its large density brings its poor dilution and worse compressibility than MCC. Although it is brittle, SDL also tends to be less fragmented. Therefore, it is as sensitive as MCC to lubricant. SDL contains part amorphous lactose, which can better compressibility of SDL. Products of Fast-Flo series also contains much amorphous lactose. However, compatibility is another problem for lactose. It is easy to react with auxiliary materials containing primary amine or secondary amine and therefore, tablets turns khaki. This process is termed Maillard Reaction.
DCP
Inorganic thinner used the most widely in DC is DCP. It has good fluidity and compressibility. DCP, a brittle material, is not sensitive to lubricant. It is soluble in acid instead of water and alkali. Besides, since it cannot function to disintegrate, it is not suggested to used DCP a lot when API is hardly soluble.
|
Thinner |
Level |
Tap density (g/cc) |
|
MCC |
Acicel PH102 |
0.314 |
|
Hydrous |
lactose Fast-Flo |
lactose Fast-Flo |
|
DCP |
Di-Tab |
0.993 |
