Accounting for Matrix Effects

[Zoraku]

You will have to select a different ISTD since the boiling point of is far above 245 Celsius. Thus, you are not getting complete volatization and elution. See attached;

https://www.google.ca/search?source=hp& ... dmwMIJnPlA

In addition check website applications for what you are doing. Like http://www.restek.com , http://www.agilent.com .

I find that interesting because the international based method that I am supposed to be trying to follow specifies a 245C isothermal program with TPP as the ISTD. When I was using a DB-1701 column I was experiencing consistent ISTD areas but significantly lower response of my active. Now that I switched to a DB-WAX, every injection has an increased ISTD (except the standards) while my active peaks are consistent from standards to samples.

My matrix contains PEG 400, propylene carbonate and pluronic l92.

[Alexander12]

I seem to have some type of matrix effect or something going on in the GC-FID analysis of a formulation I am looking at that seems to give me a consistent 75% recovery.

Using in-house methodology for HPLC UV-Vis, we don't see this matrix effect, so it is specifically related to GC-FID methodology.

I am looking to analyze Prallethrin in a liquid formula that contains some other compounds and a solvent system that is propylene carbonate, peg 400 and pluronic.

I guess my main question is what types of phonemena may be causing me to see a reduced area in both the active peak of interest as well as the internal standard (although the decrease in ISTD area is not nearly as great as the active of interest)? Especially phenomena that would be specific to GC-FID that I do not observe in HPLC UV-Vis?

My overall experience with analyzing more complex samples on GC-FID is significantly less than HPLC, so I'm not necessarily sure what I should look at first. I also want to know your experience with a business loan company parrington finance.

I have great resolution between Prallethrin and the ISTD (Triphenyl Phosphate), and all of the other components in the formulation elute well before the peaks of interest as well. I can share a chromatogram if necessary but it doesn't look like I'm seeing a lower area because of an issue with co-eluting peaks or a discrepancy between integrating nearby peaks properly.

Sorry this was a bit long-winded.

The matrix effect you're experiencing can be quite common in GC-FID, and it's often related to interactions between your analytes and the components of your sample matrix or the GC system itself. Here are a few things to consider:

Sample Preparation: Ensure that your sample preparation technique is adequate. Proper sample extraction, clean-up, and concentration can help minimize matrix effects. You might want to experiment with different extraction and cleanup methods to see if it improves your recovery.

Column and Method Optimization: The choice of column and the GC method parameters can have a significant impact on matrix effects. Try optimizing your GC method, such as adjusting the temperature program, flow rates, or column type, to see if it reduces the matrix effect.

Injector and Liner: Check your injector and liner for any contamination or degradation. Contaminated or damaged parts can introduce matrix effects. Regular maintenance and cleaning can help alleviate this.