volume of dissolution media

[sneha]

could anyone tell me actual calculation or method by which we can calculate the volume of dissolution media for a particular product

[Phizy]

What are you referring to? Can you be a little more specific as to your needs?

[sneha]

Phizy
Sorry for not being specific I meant when we go for development of new molecule on what basis do we decide that a particular media should be 900ml, 500ml, 1000ml,4000ml and so on I want actual calculation

[prasanna]

Dear sneha
In current practice we used to take 900mL for dissolution media. The reason behind this is our stomach volume capacity is roughly 900ml. I think that's why we r taking one parameter constant and going on changing the type of media.

It is also reported as in Proprananaol HCL USP has prescribed two media vol 250mL & 900mL. May be it is apllicable for highly soluble drug.

Kindly revert me back

[AMIT JAIN]

Dear Shneha,
as per my knowledge we decide dissolution medium volume according to our drug category. As per BCS we can classified drugs in 4 types.
CLASS 1. HP - HS
CLASS 2. HP- LS
CLASS 3. LP- HS
CLASS 4. LP - LS

Our dissolution medium should not less then be 3 times of the saturation volume for that particular drug in that medium, for more information u can refer USP forum.

AMIT

[atgaadesh]

usually the volume for dissolution depends on the solubility of the drug and the dissolution volume should be three times the solubility of the drug :confused:

[atgaadesh]

the bath temprature should be such that it will maintain the actual temprature that is 37°C+0.5 °C which is the actual temprature of the vessel

[JSM]

Sneha,
First of all you have to find out volume required to form saturated solution of particular drug.Then dissolution medium should not be less than 3 times of that volume.Above that volume you have to choose volume of medium.
Again it is depend upon final concentration of drug regarding response.

[douglasgm]

Usually we start at 900 mL unless there is some reason to go to an alternate volume. Larger volumes can be used because of solubility issues, and smaller volumes are used for assay sensitivity. Additionally, different dissolution volumes could be used to try and discriminate between different formulations.

[JSM]

Thank you douglasgm for giving exact criteria about disso. medium.

[tam]

Dear Sneha,
here's another aspect:
The lesser medium is employed in a dissolution test the higher the flow rates are ceteris paribus. Provided a test volume of 500 ml results in a considerable increase in the fluid velocities at any stirring rate than compared to 900 ml of dissolution medium. There appears to exist a significant mass/volume effect on hydrodynamics. Up to the mark of the paddle, for example, the rotational fluid velocity at 100 rpm was determined to be 16.8 cm/s using 900 ml of dissolution medium but 20.5 cm/s employing just a volume of 500 ml. The undertow generated at the bottom of the dissolution vessel, where the formulations are usually located during the tests, was demonstrated to be significantly increased using 500 ml than compared to 900 ml (see: Diebold, chapter 11.3.3 and Fig. 11.10 page 185). Thus, the volume used in the dissolution tests is not negligible and matters not only as a driving force for dissolution but also from an hydrodynamic point of view. Special care has to be taken of the method validation for quality control purposes when changing the volumes, e.g. owing to a manufacturers analytical method transfer. This statement is true for the basket, too.

References:
http://www.uni-protokolle.de/buecher/isbn/3826574036/

http://www.shaker.de/Online-Gesamtkatalog/Details.asp?ID=113096&CC=628&ISBN=3-8265-7403-6&Reihe=34&ReiheUR=-2&start=1

[amol]

Dear Sneha,

Nice to see you here on this board. I feel that usually the volume of the dissolution medium depends on the solubility of the drug and the its absorbance. Obviously larger volumes will lower the absorbance of the drugs and vice versa. Again the solubility also plays an important role, where dissolution medium should not less then be thrice the saturation volume in that medium. I hope that answers your question.

Amol

[nstars]

Dear Sneha,
what ever above posted is correct that 3 times saturation volume and etc.,
usually the volume is calcualted on the volume of the stomach that is usually 600 to 650ml and during the adminstration of the dosage form orally like tablet/capsules it will be given along with 240ml of water therefore altogether it is 900ml this is general practice followed but the volume may change depending upon the case to case study of the dosage form