giang nidqc
☆    

Vietnam,
2018-09-10 11:39
(2026 d 04:19 ago)

Posting: # 19254
Views: 4,130
 

 Simultaneous analytical method [Bioanalytics]

Dear all,
In my lab, we have validated an analytical method for simultaneous determination of 5 AIs.
Can we use this method for the determination of less than 5 AIs (ex: AI 1 and AI 3).
Is there any other requirements for doing this?
Regard,
Obinoscopy
★    

USA,
2018-09-11 23:22
(2024 d 16:35 ago)

@ giang nidqc
Posting: # 19261
Views: 3,663
 

 Simultaneous analytical method

Dear Giang,

Do you mean API? The only thing that comes to my head when you mention AI is Artificial Intelligence :-)

If you were referring to API, I wonder how you were able to perform an analytical run on all 5 analytes simultaneously. Can you explain how you did it?

Scopy
giang nidqc
☆    

Vietnam,
2018-09-12 05:37
(2024 d 10:20 ago)

@ Obinoscopy
Posting: # 19266
Views: 3,756
 

 Simultaneous analytical method

Dear Obinoscopy,

❝ Do you mean API?


Yes. I meant APIs

❝ If you were referring to API, I wonder how you were able to perform an analytical run on all 5 analytes simultaneously. Can you explain how you did it?


It's a bioanalytical method for determination of 5 anti-TB drugs by LC-MS/MS. One just raise the question: Can we apply this method for just 2/3 APIs? Is there any infuence or differences? Do we need to revalidate the method, partial or full, and which criteria? Many thanks!
Obinoscopy
★    

USA,
2018-09-12 11:35
(2024 d 04:22 ago)

@ giang nidqc
Posting: # 19268
Views: 3,715
 

 Simultaneous analytical method

Dear Giang

❝ It's a bioanalytical method for determination of 5 anti-TB drugs by LC-MS/MS. One just raise the question: Can we apply this method for just 2/3 APIs? Is there any infuence or differences? Do we need to revalidate the method, partial or full, and which criteria? Many thanks!


I don't think you need to revalidate as long as the 2/3 APIs were among the 5 APIs that were validated.

But if I may ask, did you include all the CCs and QCs for the entire 5 APIs in the same analytical run?

Scopy
giang nidqc
☆    

Vietnam,
2018-09-13 05:50
(2023 d 10:07 ago)

@ Obinoscopy
Posting: # 19284
Views: 3,675
 

 Simultaneous analytical method

Dear Obinoscopy

❝ I don't think you need to revalidate as long as the 2/3 APIs were among the 5 APIs that were validated.


Could it be a possibility that the absence of one APIs may affect the final concentration of other APIs (regarding sample preparation and peak response)?
Helmut
★★★
avatar
Homepage
Vienna, Austria,
2018-09-13 13:25
(2023 d 02:33 ago)

@ giang nidqc
Posting: # 19285
Views: 3,682
 

 Simultaneous analytical method

Hi giang nidqc,

❝ Could it be a possibility that the absence of one APIs may affect the final concentration of other APIs (regarding sample preparation and peak response)?


Sample preparation

Impossible. Regardless whether you use LLE or SPE each analyte follows the law of mass action (driven by pH, lipophilicity) independent from other analytes. The amount of the “target phase” (organic solvent, RP- or exchange resin) is 6 to 12 orders of magnitude higher than the one of the analyte. Hence, the presence / absence of other analyte(s) in a similar – low – amount is simply irrelevant. It can never change the equilibrium constant.

Chromatography

Unless you have an insufficient separation, no. Only if peaks overlap, in MS ion-suppression/enhancement by one analyte could influence the response of the other.

Ligand-binding assays

Can be problematic if you have a substantial degree of cross-reactivity.


Dif-tor heh smusma 🖖🏼 Довге життя Україна! [image]
Helmut Schütz
[image]

The quality of responses received is directly proportional to the quality of the question asked. 🚮
Science Quotes
Ohlbe
★★★

France,
2018-09-13 16:06
(2022 d 23:51 ago)

@ giang nidqc
Posting: # 19287
Views: 3,655
 

 Simultaneous analytical method

Dear giang nidqc

❝ Could it be a possibility that the absence of one APIs may affect the final concentration of other APIs (regarding sample preparation and peak response)?


I agree with Helmut's post above. There is just one thing I'm thinking of: how was the spiking of calibration and QC samples done when you used 5 analytes ? Did you use a single spiking solution containing all analytes (usual practice), or separate working solutions ? If you used a single, combined solution at each level concentration, no problem. If you used separate spiking solutions, you will have a different proportion of solvent added to the plasma if you have less analytes, which may influence your recovery and matrix effects.

Regards
Ohlbe
UA Flag
Activity
 Admin contact
22,957 posts in 4,819 threads, 1,638 registered users;
77 visitors (0 registered, 77 guests [including 12 identified bots]).
Forum time: 14:58 CET (Europe/Vienna)

Nothing shows a lack of mathematical education more
than an overly precise calculation.    Carl Friedrich Gauß

The Bioequivalence and Bioavailability Forum is hosted by
BEBAC Ing. Helmut Schütz
HTML5