usp467 class1 class 2A mixture

[dogcatlike]

Why in system suitability test usp467，should inject class1 standard，class1 system suitability solution，class2A mixture，before every assay？I think it’s a waste，the standards both expensive。Is it meaningful？

For 2A standard，just check resolution between two components。Can I make the two components’ solution myself as substitution？

[krickos]

Not at work so cannot double check but as I recall:

Test one is for sensitivity S/N testing
Test 2 is for resolution.

So in general both SSTs are meaningful for column/system performance.

Search on FDAs home page, there is a Question and answer section when USP updated residual solvents chapter, look there for details, FDA allows you to purchase cheaper individual high purity standards in short.

[dogcatlike]

i can prepare the solution myself。for class1 just Carbon tetrachloride is a challenge and necessary，and 2A resolution just Acetonitrile and Methylene chloride is necessary。also，if i have validated my method no problem in S/N and resolution，necessary inject the two standard before each assay？usually in my sample not exist any class1 solvent，and not have Acetonitrile and Methylene chloride ，why i should meet the requirement？

in my opinion，the components in my drug substance have enough resolution，that's enough。

[krickos]

'




Hi

Now are you following the general procedures in USP or have you validated your own procedure? That is what decides if you have to do the USP SST or not.

If you follw/refer to USP the SSTs have to performed regardless if it is the solvents you actually are looking for or not.

Have you validated your own procedure, establishing relevant SSTs is a part of the validation and consequently you can base those on the residual solvents of interest.

I see no middle way here, but understand your argumentation. Thats one of several reasons why many companies validate their own procedure for routine analysis.

[chromatographer1]

dogcatlike

Now do you see why I can't imagine any competent company using the USP test routinely? And why it is better to validate your own test?

Either you follow the USP or you don't. You don't get to pick and choose and then get to state you followed the USP test.

Do it all, or DON'T DO IT !

GOOD LUCK,

Rod

[dogcatlike]

dogcatlike

Now do you see why I can't imagine any competent company using the USP test routinely? And why it is better to validate your own test?

Either you follow the USP or you don't. You don't get to pick and choose and then get to state you followed the USP test.

Do it all, or DON'T DO IT !

GOOD LUCK,

Rod

“validate your own test“ is very challenge？i can develop my method based on 467，such as shorten oven temp time，not inject the two kind standards？what like method is good？based on what criterion？how to prove a method effective and excellent？

[chromatographer1]

You need to read and understand the USP requirements of a test method.

Or contract a chemist or a company to supply you with a validation protocol and validation results in a suitable documented format.

It is not merely coming up with a set of instrument parameters that seem to work, although that is an important factor.

There are books available, but reading the USP is the best place to start.

best wishes,

Rod

[dogcatlike]

'




Hi

Now are you following the general procedures in USP or have you validated your own procedure? That is what decides if you have to do the USP SST or not.

If you follw/refer to USP the SSTs have to performed regardless if it is the solvents you actually are looking for or not.

Have you validated your own procedure, establishing relevant SSTs is a part of the validation and consequently you can base those on the residual solvents of interest.

I see no middle way here, but understand your argumentation. Thats one of several reasons why many companies validate their own procedure for routine analysis.

thanks。even totally follow 467，for every new drug substance，i still have to validate my method ，as our company regulation。some difference to 'validate their own procedure'？i'm fresh man, don't know much in analysis field.

[dogcatlike]

You need to read and understand the USP requirements of a test method.

Or contract a chemist or a company to supply you with a validation protocol and validation results in a suitable documented format.

It is not merely coming up with a set of instrument parameters that seem to work, although that is an important factor.

There are books available, but reading the USP is the best place to start.

best wishes,

Rod

why u know so much? a expert. if have a master beside me, guide me, that will be fabulous.
which chapter about this content ? i need to learn too much things. u say, "validate ur own method" it's general and widely accepted，or just a few company？

[chromatographer1]

I do not have a copy of the USP book with me.

There is a section detailing the requirements of a proper validation of an analytical method. Check the table of contents in your copy to review the section.

Yes, there are many requirements to authoring a validation method. Discuss this with the USP, I am sure there are representatives in the USP who would guide you concerning their requirements and would tutor you. You want a method validation that the USP would consider acceptable to their review.

Many smaller companies do not wish to hire the level of expertise to perform these tasks for validation professionals have high salaries. It is easier to use the USP methods, but is not cheaper actually over the long haul, although it looks like it would be to the company management. Of course, they don't do the actual lab work involved.

best wishes,

Rod

[dogcatlike]

I do not have a copy of the USP book with me.

There is a section detailing the requirements of a proper validation of an analytical method. Check the table of contents in your copy to review the section.

Yes, there are many requirements to authoring a validation method. Discuss this with the USP, I am sure there are representatives in the USP who would guide you concerning their requirements and would tutor you. You want a method validation that the USP would consider acceptable to their review.

Many smaller companies do not wish to hire the level of expertise to perform these tasks for validation professionals have high salaries. It is easier to use the USP methods, but is not cheaper actually over the long haul, although it looks like it would be to the company management. Of course, they don't do the actual lab work involved.

best wishes,

Rod

thanks rod， you are always hot hearted and active。it seems not easy to validate a new method，which surpass our ability of little firm，so i give up the idea。i just try my best to follow USP467，manage to resolve emerging problem。i hope can gain help of friends in forum。

[dogcatlike]

I do not have a copy of the USP book with me.

There is a section detailing the requirements of a proper validation of an analytical method. Check the table of contents in your copy to review the section.

Yes, there are many requirements to authoring a validation method. Discuss this with the USP, I am sure there are representatives in the USP who would guide you concerning their requirements and would tutor you. You want a method validation that the USP would consider acceptable to their review.

Many smaller companies do not wish to hire the level of expertise to perform these tasks for validation professionals have high salaries. It is easier to use the USP methods, but is not cheaper actually over the long haul, although it looks like it would be to the company management. Of course, they don't do the actual lab work involved.

best wishes,

Rod

thanks rod， you are always hot hearted and active。it seems not easy to validate a new method，which surpass our ability of little firm，so i give up the idea。i just try my best to follow USP467，manage to resolve emerging problem。i hope can gain help of friends in forum。