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Checking of LOD

can anyone tell me the actual procedure of checking of Loss On Drying in a drying process after wet granulation. as the sample will be wet and not uniform in size so what is the actual procedure? should the sample be sifted thro’ any sieve that is gonna be used for sifting after drying or what is the procedure? plz clarify

Yes, its practicle issue but for better control u can check LOD after Wet granules milling to see uniform distribution of binder.For this please collect data of LOD immediate after wet granulation and after wet milling also.Based on comparative data you can co-related it.

Dear Piyush

Can you tell me what should be the ideal set temperature (70/95/105 degree C) required while checking LOD in IR moisture analyser (at constant weight)when we dont have any recommended drying profile in our reference documents ?

Dear All

Please note that after wet granulation u better keep the granules in suitable dryer after its sizing through suitable mesh. let it be dried in tray drier or Fluid bed dryer. unless the target of Not less than 2% moisture is achieved, to test LOD is useless to check it initially its better to check it after some drying. and it should be established during development stage and process validation.

The suitable temperature and time for the IR moisture balance is 105°C for 10 minutes but its not always recommended it depends according to the matrix nature, like in sugar, LOD checking is done with 80° C to avoid its charring. so it depends and to be stablished during development stage of formulation, u can have a profile of 80 to 105° C and definitely Holding time will vary accordingly.


Shahid Ali
QA Manager
Addis Pharmaceutical Factory SC, Ethipia

Nice and precise answer Mr Shahid.