Overview of the hottest drug tablets and its packa

Overview of pharmaceutical tablets and their packaging technology application III

v. evaluation of tablets:

1 Hardness:

2 Brittleness: the tablet is easy to cause fragments, top cracks, cracks, etc. after being vibrated or rubbed. Brittleness reflects the anti-wear and vibration ability of tablets, and it is also an important item of tablet quality standard inspection

VI. factors affecting tablet forming:

l. compression formability compression formability is the ability of materials to form a certain shape after being compressed. The preparation process of tablets is the mixing of substances and excipients. Although the limit switch is only applicable to the time when the speed is not very high (2) the process of digging a pit down from the installation position of the experimental machine and compressing it into a solid aggregate with a certain shape and size. Most drugs produce plastic deformation and elastic deformation when they are added. Their plastic deformation produces binding force and is easy to form; Its elastic deformation does not produce bonding and tends to return to its original shape, thus weakening or disintegrating the bonding force of the tablet, and even cracking and loosening occur

2. The low melting point of the drug is conducive to the formation of "solid bridge", but the low melting point makes the tablet easy to stick and impact; Cubic crystal system has good crystal symmetry and large surface area, which is easy to form when compressed; Flake or acicular crystals are easy to arrange in layers, so compressed tablets are easy to crack; Dendritic crystals are easy to deform and are embedded with each other, and the compressibility is easy to form, but the disadvantage is that the fluidity is very poor

3 adhesives and lubricants adhesives enhance the binding force between particles and are easy to compress and form, but they are easy to stick when used too much, which will affect the disintegration of tablets and the dissolution of drugs. The commonly used lubricant is hydrophobic substance (such as magnesium stearate), which weakens the force between particles, but has little effect on the formation of tablets within its commonly used concentration range

4 moisture an appropriate amount of moisture is squeezed onto the surface of the particles to form a film during compression, making the particles easy to get close to each other, but excessive moisture is easy to cause stick impact. In addition, water content can dissolve the soluble components on the surface of the particles. When the tablets lose water, recrystallization occurs and a "solid bridge" is built between adjacent particles, thereby increasing the hardness of the tablets

5. generally, the greater the pressure is, the closer the distance between particles is, the stronger the adhesion is, and the hardness of the pressed tablet is also. However, when the pressure exceeds a certain range, the influence of pressure on the hardness of the tablet decreases, and even cracks appear

VII. Possible problems and cause analysis in tablet preparation

1 The phenomenon that a tablet splits is called a split. If the split position occurs in the upper or middle of the tablet

2. Loose tablets are not hard enough, and the phenomenon that they break up after a little touch is called loose tablets. The main reasons are the difference of viscous force and insufficient pressure of pressure flange

3. Sticking and punching a thin layer or a small part of the surface of the tablet is stuck by the punch, causing one side to be rough or dented, which is now called sticking and punching (Fig. C); If the edge of the tablet is rough or there is a flaw, it can be called wall sticking accordingly (Fig. d). The main reasons for sticking or sticking to the wall are: the particles are not dry enough, the materials are easy to absorb moisture, the lubricant is improperly selected or insufficient, the punch table is rusted, rough or engraved, etc., which should be solved according to the actual situation

4. Slice weight difference exceeds the limit

5 Slow disintegration. Generally, oral tablets should disintegrate rapidly in the gastrointestinal tract. If the tablet exceeds the prescribed disintegration time limit, it is called disintegration over limit or disintegration delay

6. Dissolution out of limit tablets can not dissolve the specified amount of drugs within the specified time, that is, dissolution out of limit or known as rongkouyu. The main fear factors of the dissolution of shadow ah about substances are: the tablets do not disintegrate, the right bar is too hard, the pan dissolution of drugs is poor, etc., which should be solved according to the situation

7. The uneven drug content in tablets can be caused by all factors that cause excessive differences in tablet weight. For low-dose drugs, in addition to uneven mixing, the migration of soluble components between particles is an important reason for their unqualified uniformity

(I) multiple doses and packaging

1 Glass bottles are the most widely used packaging containers. Its advantages are good sealing, impermeable to steam and air, chemically inert, not easy to deteriorate, low price, and colored glass bottles have a certain role in avoiding light. Its disadvantage is that it is heavy and easy to be damaged

2. The advantages of plastic bottles are light texture, not easy to break, easy to make various shapes, beautiful appearance, etc. its disadvantages are that the isolation performance is not as good as glass products, and deformation may occur under high temperature and high humidity

(II) single dose packaging

is divided into blister type (also known as blister eye) packaging and narrow strip packaging. Each tablet is packaged individually, so that each drug is in a sealed state, which improves the protective effect of the product and also eliminates cross contamination

cases of compound sulfamethoxazole tablets (compound sulfamethoxazole tablets)

[prescription] sulfamethoxazole (SMN) 400g

trimethoxycarbamate (TMP) 80g

starch 40g,

10% starch 24g

dry starch 23g (about 4%)

magnesium stearate 3G (0.5% left and right)

made into 1000 tablets (each tablet contains smz0.4g)

[preparation] SMZ and TMP are sieved through 80 mesh sieve, mixed with starch, and added with starch T. the shear stress unit is MPa to make soft material, Granulate with 14 mesh sieve, dry at 70 ~ 80 ℃, sieve the whole granule with 12 mesh sieve, add dry starch and magnesium stearate, mix well, and then press the tablet

2. Tablets of unstable drugs

example: compound glyphthalic salicylic acid tablets

[prescription L glyphthalic salicylic acid (aspirin) 268g

paracetamol (paracetamol) 136g

caffeine 33.4g

starch 2669

starch paste (15 ~ 17%) 85g

talc powder 25g (5%)

light liquid paraffin 2.5G

tartaric acid 2.7g

make 1000 tablets

3. Tablets of low-dose drugs

example: nitroglycerin tablets

[prescription] Lactose 88.8g

powdered sugar 38.0g

17% starch proper amount

10% nitroglycerin ethanol solution 0.6g (nitroglycerin content)

the recovery rate of stearic metal can reach more than 97%. Magnesium sulfate 1.0g

is made into 1000 tablets (each tablet contains 0.5mg nitroglycerin)

[preparation] first prepare blank particles, and then make Nitroglycerin into 10 intestines of ethanol solution (120% feeding) mixed with the fine powder of blank particles (below 30 meshes), and sift twice through 10 meshes.After, Dry it below 40 ℃ for 50 ~ 6omin, then mix it with the blank particles and magnesium stearate prepared in advance, and press the tablets

[note] this is a tablet of low-dose drugs for the treatment of angina pectoris through sublingual absorption, and it is not suitable to add insoluble excipients (except a small amount of magnesium stearate as a lubricant)

in order to prevent the content uniformity from being unqualified due to uneven mixing, the main drug ethanol is added (of course, it can also be sprayed) into the blank particles. During the preparation, attention should also be paid to prevent vibration, heating and suction, so as to avoid explosion and severe headache of operators. In addition, this product is an emergency medicine, and the tablet should not be too hard, so as not to affect its instant solubility

(to be continued)