Direct Compression is the ingredients of a mixture of pulverulent materials without initial process. The advantage of this method is that the ingredients are moist and heat sensitive, that stability operations disrupted by granulation can be made into tablets. But only a few drugs that can be made by direct compression, without further processing and without excipient. If at the time of compression produces a small tablet form, it is caused by the formation of cohesive force between powder particles during compression.

Excipient should be to improve the flow properties and through holding capacity enhancements allow printing of compact powder and cause mold.

In this experiment, the compressing method used is Theophylline because Theophylline has a good flow properties. Supplies are used as filler is Avicel. Avicel is used as filler because of the good flowability so as to reduce the deviation of mass, a high swelling power causes a short tablet disintegration time. Avicel insoluble in water, can be made very pure, chemically neutral and is a poor medium for microorganisms.

Other excipient is starch, which is used as disintegrant with a look at the literature, it turns starch has long been known that some compounds can be compressed after addition of 10-12% starch. Addition of starch to function as a regulator of the flow as well as binders.

Talc is used as glidant, because the task of the talc is to improve the flow of material to be compressed. Reducing the mass deviation and increase the accuracy of the size of the tablet. Mg stearate is used as a lubricant to reduce friction of metal and friction making it easier for expenditure the tablets from the mold.

Background Formula
Direct Compressing method is generally used for active substance that is thermolabile, has poor solubility with the solvent and has a particularly small doses. But, shortages of medicines that made of direct compressing with small doses is not evenly mixed with other components. While for large doses of the active substance can not be used because the attraction force between molecules is weak or covered by a gas that is absorbed and tend to impede cohesiveness of the tablet.

Therefore, the use of filler in this method is very important, because the filler materials that can be compressed directly is the material that is neutral, eg: Avicel 102. In addition excipients used are:

Starch: a destroyer, was chosen because the starch is a material fast contact with gastric fluid so that the tablet can be quickly destroyed Dena release the active ingredient.
Mg stearate: as a lubricant, is used to reduce friction between the drugs with the printing press, was chosen because of magnesium stearate is the best lubricant than amino-acid.
Talcum: as glidan (lubricant) is used to reduce inter-particle cohesion when compressed so it can provide good flow properties.

Active ingredient
Molecular formula: C7H8N4O2.H2O
Molecular Weight: 198.18
Description: fibrous or granular powder, white colored, suspension in water reacts neutral to litmus P, swell in water and form a clear suspension until viscous, colloidal
Solubility: difficult to dissolve in water but easily soluble in alkali hydroxide solution and the ammonium hydroxide is somewhat difficult soluble in ethanol.
Stability: can be stored at room temperature, under light fluorosence continuous period of at - least 180 days without a significant change in concentration in the solution should be protected form the light, stable in air.
Benefits: asthma medication, CNS and respiratory stimulation, stimulation of the heart to work as a diuretic is weak.
Incompatibility: Tanin
Storage: in well sealed containers
Dose: for slow release dosage adult and children 400mg/hr max. 125-250 mg 3-4 dd

Avicel PH 102
Description : white powder, odorless
Molecular formula: (C6H10O5) n
Molecular Weight:> 3100
Solubility: practically insoluble in water, dilute acids, organic solvents and 5% NaOH
Uses: filler and binder (Filler - Binder)
Concentration: 20-90%
Stability: hygroscopic
Storage: in well sealed container, in a cool and dry.
Avicel is a good filler for direct compression and dry granulation. Avicel can absorb moisture the air so high. Binding ability (holding capacity) 50%
100 mg of active substance, then the minimum required Avicel
50% = 100 / 50 x 100 mg = 200 mg

Amylum maydis
Description:odourless and tasteless, fine and white powder
Solubility: practically insoluble in cold 95% ethanol and cold water.
Spesific gravity bulk: 0.462 gram/cm3
Spesific gravity incompressible: 0.658 gram/cm3
Incompatibility: inert material
Concentration: 3-15%
Purpose: Diluent
Storage: in well sealed container, in a cool, dry

Mg stearate
Molecular formula: C16H70MgO4
Desciption: powder is smooth, easily attached to the skin, has the sense of typical weak baud
Solubility: practically insoluble in water
Stability: stable and store in a dry place
Incompatibility: with a strong acid, salt - the salt of iron, and avoid mixing with strong oxidizing
Concentration: 0,25 - 5.0%
Purpose: lubricant / lubricant substance
Storage: in sealed and a cool place

Molecular formula: Mg6 (SiO5) (OH) 4
Description: very fine white crystalline powder or white-gray, shiny, easily attached to the skin and free from grain.
Solubility: practically insoluble in water, weak acids and bases and organic solvents.
Stability: stable and can be sterilized by heating for at least 160 degrees for 1 hour
Incompatibility: with quaternary ammonium component
Concentration: 10-10%
Purpose: glidant
Storage: in well sealed containers

Theophylline 100 mg
Starch 5%
Mg stearate 1%
Talc 2%
Avicel qs

Weighing & Calculation:
Created 400 tablets: @ 350mg / tablet
The weight of the tablet = 400 x 350 mg = 140 000 mg = 140 grams
Theophylline = 400 x 100 mg = 40 grams
Starch = 5% x 140 grams = 7 grams
Mg stearate = 1% x 140 grams = 1.4 grams
Talk = 2% x 140 grams = 2.8 grams
Avicel PH 102 = 140 grams - (40 +7 +1.4 +2.8) = 88.8 grams
If Avicel have a capacity of holding 50% of the theophylline dose of 100 mg, then
Avicel = 100/50 x 100 mg = 200 mg
Avicel for 400 tablets = 400 x 200 mg = 80.000mg = 80 grams

1. Prepare the necessary tools and materials
2. Weigh the material to be used
3. Shear and mixed: theophylline, Avicel PH 102, starch ad homogeneous
4. Test granules
5. The mixture which has been tested, added with Talc and magnesium stearate, mixed homogeneous
6. Compress the tablet with tablet compressing machine
7. Perform an evaluation test tablets, enter the tablet into the container, give etiquette and submit.