-
- admin
- Site Admin
-
- Posts: 647
- Joined: Wed Aug 11, 2004 12:19 am
By julie on Tuesday, April 13, 2004 - 11:44 am:
OK, I have what is more than likely a dumb question. When is method validation required? So, if one is doing basic research and creates a method based on others, does validation need to be done?
-------------------------------------------------------------------------------------------------------
By M. Stone on Tuesday, April 13, 2004 - 05:09 pm:
Well, if you are not in a regulatory environment it is basically a matter of what you - and your coworkers - think is necessary. I think at a minimum it would be advisable to do a few quick experiments such that you can be confident that the results you get from the method are, in fact, accurate. This may involve analyzing spike recovery samples or analysis of a sample with a known quantity of material. From these same experiments you can also get a handle on what type of precision your method is giving you. That's about the best answer I can give without knowing the details of what you're doing.
-------------------------------------------------------------------------------------------------------
By tom jupille on Sunday, April 18, 2004 - 10:46 pm:
To expand a bit on the previous post: "validation" is basically proving that a method does what it purports to do. How stringent that proof needs to be depends on what you are doing.
In a "regulated" area (e.g., pharmaceuticals), the level of proof required is very high (for obvious reasons), and the steps involved are established by regulatory agencies. In basic research, validation can be as simple as a few quick recovery experiments, as suggested above. When you publish , your "validation" results should form part of the publication (and, as such, be subject to peer review). If you are a student, your research advisor should be able to point you in the right direction. If you are in industry, talk to others working in the same area to get a feel for what level of validation is expected.
-------------------------------------------------------------------------------------------------------
By Anonymous on Friday, June 18, 2004 - 12:07 pm:
How do you go about validating a standard addition method? I have an OVI mehod by GC headspace. Now it needs validated for NDA. It is obviously linear, but how would you define accuracy and LOQ? Would you report precision based on only one level? What would be the best approach?
-------------------------------------------------------------------------------------------------------
By rod on Tuesday, June 22, 2004 - 07:27 am:
Dear Anonymous
Here is my opinion. It is 5 cents worth of free advice. Use with caution and discretion at your own risk. IN OTHER WORDS, don't quote me.
You should first generate a protocol of analysis and validation and then follow it exactly. Review the latest USP requirements.
First validate and show that solvent blank standards are linear and reproducible. If this is not so, then it is not likely to be so if the drug is dissolved in the solvent. If you had a water soluble drug then show that the test is linear.... R*R ¡Ã
OK, I have what is more than likely a dumb question. When is method validation required? So, if one is doing basic research and creates a method based on others, does validation need to be done?
-------------------------------------------------------------------------------------------------------
By M. Stone on Tuesday, April 13, 2004 - 05:09 pm:
Well, if you are not in a regulatory environment it is basically a matter of what you - and your coworkers - think is necessary. I think at a minimum it would be advisable to do a few quick experiments such that you can be confident that the results you get from the method are, in fact, accurate. This may involve analyzing spike recovery samples or analysis of a sample with a known quantity of material. From these same experiments you can also get a handle on what type of precision your method is giving you. That's about the best answer I can give without knowing the details of what you're doing.
-------------------------------------------------------------------------------------------------------
By tom jupille on Sunday, April 18, 2004 - 10:46 pm:
To expand a bit on the previous post: "validation" is basically proving that a method does what it purports to do. How stringent that proof needs to be depends on what you are doing.
In a "regulated" area (e.g., pharmaceuticals), the level of proof required is very high (for obvious reasons), and the steps involved are established by regulatory agencies. In basic research, validation can be as simple as a few quick recovery experiments, as suggested above. When you publish , your "validation" results should form part of the publication (and, as such, be subject to peer review). If you are a student, your research advisor should be able to point you in the right direction. If you are in industry, talk to others working in the same area to get a feel for what level of validation is expected.
-------------------------------------------------------------------------------------------------------
By Anonymous on Friday, June 18, 2004 - 12:07 pm:
How do you go about validating a standard addition method? I have an OVI mehod by GC headspace. Now it needs validated for NDA. It is obviously linear, but how would you define accuracy and LOQ? Would you report precision based on only one level? What would be the best approach?
-------------------------------------------------------------------------------------------------------
By rod on Tuesday, June 22, 2004 - 07:27 am:
Dear Anonymous
Here is my opinion. It is 5 cents worth of free advice. Use with caution and discretion at your own risk. IN OTHER WORDS, don't quote me.
You should first generate a protocol of analysis and validation and then follow it exactly. Review the latest USP requirements.
First validate and show that solvent blank standards are linear and reproducible. If this is not so, then it is not likely to be so if the drug is dissolved in the solvent. If you had a water soluble drug then show that the test is linear.... R*R ¡Ã
