Disintegration vs. Dissolution

[MMm]

According to the ICH (Topic Q6A Specifications), Setting Acceptance criteria for drug product dissolution :

Is the dosage form dissolution rapid (>80% in 15 min at pH 1.2, 4.0 and 6.8) and a relationship has been determined between dissolution and disintegration - then the dissolution test can be replaced by the simpler disintegration test.

My questions :

At what rpm and ionstrength of the buffers do you confirm that the dissolution is > 80%?

How do you establish a relationship between dissloution and disintegration, is it necessary to deliberately manufacture "bad" tablets?

[johnt]

The tests would be performed using the prepartions specified in the USP24 under buffer preparation. The testing would be done at 50rpm paddles and 100 rpm baskets.
I would not manufacture bad tablets because you need to establish the rate of dissolution using the formulation that is intended to be marketed.

[MMm]

Thanks!

How do you practically do the correlation between dissolution and disintegration?

Are there any guidelines concerning this matter?

[rajeshdengre]

There is no guidelines for the correlation between dissolution and disintegration & test of dissolution cannt be avoided, if urs tablets is showing disintegration it doesnt mean it will show the the same dissolution.
thanks

[mac1]

Sir,
I feel DT test is only to give an idea about the pattern of disintegration that a tablet will exhibit in dissolution medium. It does not necessarily be corelated for dissolution profilke of a product.
For eg.
Case 1: if your tablet is showing dt of about 60 mins then you will not give it for dissolution testing as you know that your product will not give dissolution of required % in specified time as your tablet fails to disintegrate in 15 min. time.
Case 2: If your tablet disintegrate in specified time of 15 min. (say for IR tablets), that MEANS YOUR TABLET ACCOMPLISHED THE PREREQUISITE OF DISINTEGRATION IN SPECIFIED TIME AND SO YOU CAN NOW LOOK UP FOR NEXT parameter that is dissolution profile.
regards
MAC1

[devendra shakya]

We know that initialy dissolution test was not in practice it establised in 1970+
we used to DT for quality checkup.Now Dissolution is in practice.Guailine suggest for
such replacementTest but in case by case.nawadays, regulatory agencies require
dissolution profile rather than single point. so such type replacement will be very typical.for understandable as well as justificiable.
some formulation release drug without disintegrate and some disintegrate prior to release. another fact is that dissolution can be done by changing apparatus, speed
while DT not.
so i think dissolution is must & can not be replaced by DT