Difference Between Disintegration and Dissolution

Disintegration and dissolution are two most commonly used terms in pharma industries but most of the people do not know the exact difference between these two terms. In this article we will discuss the following,

What is Disintegration?
What is Dissolution?
Disintegration VS Dissolution
Relationship Between Disintegration and Dissolution
Factors Affecting Disintegration and Dissolution.

What is Disintegration?

Disintegration is the in vitro test which is performed by using basket rack assembly to check the rate at which the tablet breaks down into small fragments.

The process in which solid dosage forms when come in contact with fluid breaks down into small granules or fragments which pass through the mesh no #10 or 2.0±0.2 mm leaving behind no solid mass.

Explanation

Disintegration test is performed in vitro means outside the body to check that our tablets or solid dosage form breaks down properly into small fragments in a specified time period.

When we take a solid dosage form it should disintegrate properly inside the body to facilitate the process of drug release.

If we take a solid dosage form which does not disintegrate in the body will not produce the desired pharmacological effect.

The disintegration time can be adjusted using a class of excipients known as disintegrants and super disintegrants.

These disintegrants or superdisintegrants break the bondings in solid dosage forms and facilitate the drug release.

Examples

Some commonly used disintegrants and superdisintegrants are as follow,

Starch
Pregelatinized Starch
Sodium starch glycolate
Cross-carmelose Sodium.
Cross linked PVP

What is Dissolution

Dissolution is a process in which dosage forms dissolve to form a solution and the amount of drug dissolved is determined by HPLC or other analytical methods.

Dissolution is a process in which a solute in the form of gas ,liquid or solid form dissolves in a solvent to form a solution.

Explanation

The process of checking the rate at which drug dissolves in a liquid medium is known as dissolution.
When we take any dosage form orally it should properly dissolve in gastrointestinal fluid to release its active pharmaceutical ingredient and after proper dissolution of API it will reach the systemic circulation and its bioavailability will be increased.
To check the in vitro dissolution profile different types of dissolution apparatus are used for different dosage forms.

For solid dosage forms type 1 or type 2 dissolution apparatus are used where a tablet or capsule dissolves in the liquid medium and sampling of solution is done at specific time intervals to check the dissolution rate of drug.

Also Read:

100 MCQs to revise your pharmaceutical knowledge.

Disintegration VS Dissolution

Disintegration	Dissolution
It is a Physical Test.	It is a Chemical Test.
This test is Used for solid dosage forms	This test is Used for solid dosage forms,gases and liquids.
In this test Solid dosage forms breaks down into small fragments	In this test Dosage forms dissolve to form solution
In-vitro	In-vitro & In-Vivo

Relationship between Disintegration and Dissolution

Disintegration and dissolution are interrelated with each other.
There is an inverse relation between disintegration and dissolution.
If the disintegration time of solid dosage form is high the dissolution rate of that product will be low.
For getting a good dissolution profile the product should disintegrate rapidly.
Suppose we take a tablet and in the stomach it does not properly disintegrate then its dissolution profile will be low and its bioavailability will also be low.

Factors Affecting Disintegration and Dissolution.

Following are the factors which may affect the dissolution of solid dosage forms,

Amount of binder
Kneading Time
Sieve selection
Hardness

Amount of binder

Binders are the excipients which are used to convert powder into granules or in simple words binders form strong bounds and give strength to the solid dosage forms.
If the amount of binder is high then the bounding will be strong and the disintegration time will be prolonged and the dissolution profile will be low and vice versa.
So the amount of binder used should be optimum to get desired results.

Kneading Time

The process of mixing used for converting powders into granules after the addition of binder or solvent is known as kneading and the duration for which we continue this process is known as kneading time.
If the kneading time is increased the granules produced will be hard and disintegration time will be prolonged and the dissolution profile will be low.
So the kneading time should carefully be monitored to produce good quality granules.

Sieve selection

Sieve selection plays an important role for final granules size.
If we use higher mesh number like #24 it will produce small size granules.
If we use lower mesh number like #12 it will produce large granules as we know drug release from large granules is slow so dissolution is low and disintegration time is prolonged.
So the sieve is selected carefully according to tablet weight and dissolution profile.