Selection of excipients during tablet pressing process

Starch（Starch）

1. The most commonly used is corn starch, which has properties and stability that do not work with most drugs. Its moisture content is6％-8%. In practical production, it is often mixed with sugar powder and dextrin that have good compressibility, because starch has poor compressibility, and when used alone, the compressed tablets are too loose.
2. Compatibility taboos: Some drugs with strong acidity are not suitable for using starch as a filler, because wet granules can partially hydrolyze starch during the drying process, affecting the quality of tablets.

1. Sugar powder（Sucrose）Sugar powder refers to the white powder of crystalline sucrose that has been dried and crushed at low temperatures. It has strong adhesion and can be used to increase the hardness of tablets, making the surface of tablets smooth and beautiful. However, due to the strong hygroscopicity of sugar powder, long-term storage can cause the hardness of tablets to be too high, making it difficult to disintegrate or dissolve.
2. Caution: Except for oral tablets or soluble tablets, they are generally not used alone and are often used in combination with dextrin and starch.

1. Dextrin（Dextri）

Dextrin is a general term for intermediate products of starch hydrolysis, which have strong adhesion. Improper use can cause pitting, watermarking, tablet disintegration, or delayed dissolution; Insufficient crushing and extraction during content determination can affect the accuracy and reproducibility of the results, so it is rarely used alone in large quantities and is often used in combination with sugar powder and starch.

Compatibility taboos: Dextrin has weaker viscosity than sugar powder and is not suitable for fibrous medicinal powders.

Lactose（Lactose）

1. It is an excellent filler commonly found in lactose containing a crystalline water. It is non hygroscopic, has good compressibility and flowability, and produces smooth and aesthetically pleasing tablets with a good drug dissolution rate. Tablets placed in the air are not easily hygroscopic and loose, making them easy to package. Do not delay the disintegration time of tablets during storage.

Compatibility taboos: Lactose used as a tablet excipient, such as tablets compressed in combination with amine drugs, will appear brownish yellow over time When the prescription contains tartrate, citrate, acetate, etc., or under the influence of alkaline lubricants, it can accelerate the color change reaction, so attention should be paid when using it.

Compressible starch

1. It can also be called pre gelatinized starch, which is obtained by partial hydrolysis of starch. One part is intact starch granules, and the other part is condensed into spherical granules after hydrolysis and denaturation. It is a multifunctional auxiliary material with good fluidity, compressibility, self lubrication, and dry adhesion, and has good disintegration effect.
2. Attention: If used for direct powder compression, the amount of magnesium stearate should not exceed0.5%To avoid softening effects.

Microcrystalline cellulose（MCC）

1. Microcrystalline cellulose is a crystalline cellulose with a lower degree of polymerization obtained by partial hydrolysis of cellulose. It has good compressibility and functions such as adhesion, flow aid, and disintegration. Microcrystalline cellulose undergoes plastic deformation during the pressurization process, and coupled with capillary action, it is highly susceptible to water entering and breaking the binding force between particles, leading to the disintegration of the film. Tablets generally contain20%Microcrystalline cellulose disintegrates well.
2. Attention: For alkaline stearate lubricants, if the dosage is high(above0.75％)When mixed for a long time, the tablets tend to soften And it may also affect disintegration or dissolution.