dear all:
does anybody meet this kind of situation before?
we ask for a MOA from our vendor, we trying to follow the test procedure to exam the material, but it’s always can’t pass the SST or get the same result (it is normal for we use different type of instrumet).
We have to modify the parameters of the instrument for fix the problem, but if we do fix, does it still could be “method transfer”? or it is already a “whole new method”?
thanks and kindly regard
pat
Good Question.
yes, It is a part of method transfer even if you change the method parameter to get system suitability pass,
In this case you have to show method verification study( specificity, Precision)must be done.
The adjustment of method parameters you want to change must be :
According to British Pharmacopia :
Liquid chromatography
Composition of the mobile phase the amount of the minor solvent component may be adjusted by ± 30 per cent relative or ± 2 per cent absolute, whichever is the larger (see example above). No other component is altered by more than 10 per cent absolute.
pH of the aqueous component of the mobile phase ± 0.2 pH, unless otherwise stated in the monograph, or ± 1.0 pH when neutral substances are to be examined.
Concentration of salts in the buffer component of a mobile phase: ± 10 per cent.
Detector wavelength no adjustment permitted.
Stationary phase:
—column length: ± 70 per cent,
—column internal diameter: ± 25 per cent,
—particle size: maximal reduction of 50 per cent, no increase permitted.
Flow rate ± 50 per cent. When in a monograph the retention time of the principle peak is indicated, the flow rate has to be adjusted if the column internal diameter has been changed. No decrease of flow rate is permitted if the monograph uses apparent number of theoretical plates in the qualification section.
Temperature ± 10 per cent, to a maximum of 60 °C.
Injection volume may be decreased, provided detection and repeatability of the peak(s) to be determined are satisfactory.
Gradient elution the configuration of the equipment employed may significantly alter the resolution, retention time and relative retentions described in the method. Should this occur, it may be due to excessive dwell volume which is the volume between the point at which the 2 eluants meet and the top of the column.
Gas chromatography
Stationary phase:
—column length: ± 70 per cent,
—column internal diameter: ± 50 per cent,
—particle size: maximal reduction of 50 per cent, no increase permitted,
—film thickness: - 50 per cent to + 100 per cent.
Flow rate ± 50 per cent.
Temperature ± 10 per cent.
Injection volume may be decreased, provided detection and repeatability are satisfactory.
According to USP, Refer the general chapter No.621
Regards,
Bujji Kanchi.