In a pharmaceutical preparation, in addition to the active ingredient drug products also required excipients / additives. The excipient is an ingredient other than the active substance added in the formulation of a drug preparation for various purposes or functions. Although excipients are not the active substances, excipients are essential in pharmaceutical production to enhance the acceptability of patient.
IPEC (The International Pharmaceutical Excipients Council) divides the excipients for solid preparations in several general categories based on their functions, there are: binders, disintegrant, fillers, lubricants, glidant, dyes, sweeteners, preservatives, suspending agents / dispersants, antioxidant, and coating material.
Excipients or additives in drug are defined as additives used to convert the active ingredient into the appropriate pharmaceutical preparation form for use in the patient. The International Pharmaceutical Excipients Council (IPEC) defines Pharmaceutical excipients as non-drug or pro-drug substances that have been evaluated for safety and are intended for drug delivery systems for the following purposes:
- To assist during the manufacturing process
- Protect, support and improve stability and bioavailability of drug
- To assist in product identification
- Improve product safety and effectiveness during drug distribution and usage
Some of the most common general criteria for excipients are it must be physiologically neutral, physically and chemically stable, comply with legislation, do not affect the bioavailability of the drug, are free of pathogenic microbes and are available in sufficient quantities and are inexpensive.
Some experts also stated that excipients are the pharmacologically inert substances that are used as additives in drug formulations especially in tablet form to improve the properties of active substances, forming tablets and facilitating tablet-making technology.
At this time we will discuss excipients within the pharmaceutical form of tablets in particular. Excipients have a very important role or function in tablet formulation. This is because there is no single active substance that can be directly compressed into a tablet without the need for excipients. Therefore, we would like to explain more about the additional ingredients that can be encountered in the manufacture of drugs below.
1. Binders
Binders serve to provide adhesion to the mass of powders in granulation and direct compression of tablet and to increase the cohesion that is already present in the filler agent. The binder may be added in the dry form and the solution form (more effectively). The binder in general can be distinguished into: natural binders, synthetic / semisynthetic polymers and sugars.
In wet granulation, the binder is usually added in solution form (made solution, muchilago or suspension), but can also be added in dry form, after mixing with the mass to be granulated with added solvent.
Binders that is usually used is mucilago Gummi Arabici 10 -20% (hot solution of Methyl cellulose 5%). The other binders that may be found in tablet are:
- Polymers (cellulose derivatives)
- CMC Na
- Gelatin
- Gom Nature
- Acacia
- Tragakan
- Guar
- Pectin
- Amylum
- Pregelatin Amylum
- Sucrose
- Others
- Corn syrup
- PEG
- Na Alginat
- Magnesium aluminum silicate
2. Disintegrant
The bioavailability of a tablet depends on the absorption of the drug. Drug absorption depends on drug solubility in gastrointestinal fluid and drug permeability across the membrane. The solubility rate of a drug in a tablet depends on the physico-chemical properties of the drug, as well as the speed of disintegration and dissolution of the tablet. To accelerate the disintegration of tablets, then added disintegrant. The disintegrant will assist the destruction of the tablet into granules, furthermore particles of the constituent particles thereby increasing the speed of tablet dissolution.
The disintegrant may be added directly (in direct stick) or may be added intragranularly, extragranularly and intra-extra combination to granulation. Disintegrant acts in destroying tablets with several mechanisms, namely: capillary action, swelling / development, heat of wetting, particle repulsive forces, deformation, release of gases, enzymatic action.
The usually used disintegrant in tablet preparation are dry manihot starch, gelatinum, sodium alginate, Amylum, Amylum 1500, Avicel (microcrystalline cellulose), Solka floc, Alginic acid, Explotab (sodium starch glycolate), Gom guar, Policlar AT (Crosslinked PVP), Amberlite IPR 88, Methylcellulose, CMC, HPMC.
3. Filler
Filler in drug formulation serves to enlarge the mass volume of drug to make it easy to be compressed or produced. Fillers are added if the active ingredients are slightly harder to be compressed. The usually used filler in drug preparation are Saccharum lactis, Amylum manihot, calcium phospas, calcii carbonas and other suitable substances.
There are fillers that can be used also as the binder, and they are called filler-binders. Filler-binders is a filler that also has the ability to increase the flow power and compactability of tablet mass. Filler binders are used in direct compression. The requirement of a material to have a function as a filler-binders is to have good fluidity and compactibility. The material having such properties usually has a relatively large particle size (not in fines form) with a spherical shape. Fillers that can have a function as filler-binders are usually modified, including co-processed diluents. Co-processed diluents are modified materials and combinations of 2 or more materials with appropriate processes.
The examples of filler-binder are calcium sulfate, amylum, microcrystaline celulose, calcium carbonate, mannitol, sucrose, dextrose, sorbitol, modification of amylum.
SOURCE: https://azchemistry.com/chemicals-used-in-medicine
TO BE CONTINUED
