With the introduction of the Resolution Labs PAL system working with the Lucidity GC-FID, we get a lot of requests to do Residual Solvents by Headspace injection. So, I purchased a standard, and got to work.
Residual solvent testing is an important test done in the pharmaceutical industry. During either the manufacture of the active pharmaceutical ingredient (API) or in the formulation of the final medication, a solvent may be used. These solvents can be toxic and compromise the safety and quality of the product. Manufacturers are responsible for ensuring their products meet the requirements for drug approval in their country.
The GC-FID program is as follows:
| Lucidity GC-FID Conditions | |||
|---|---|---|---|
| Carrier | Hydrogen | ||
| Control | Pressure | ||
| Flow | 1.5 mL/min | ||
| Split ratio | 5:1 | ||
| Column | Rtx-624 | 30 m x 0.25 mm, 1.40 um | |
| Injector | 140 ℃ | ||
| Incubation Temperature | 80 ℃ | ||
| Incubation Time | 45 min | ||
| Syringe Temperature | 105 ℃ | ||
| FID | 250 ℃ | ||
| Oven Program | |||
| Rate | Temperature | Hold Time | |
| 40 ℃ | 20 min | ||
| 10 ℃/min | 240 ℃ | 20 min | |
While not exactly the USP monograph, I did try to keep as many parameters the same to prove that the Lucidity GC-FID could run this monograph with no problems. The one change that was made was the column, because I didn’t have the correct column on hand.
Lucidity GC-FID with PAL autosampler
Chromatogram of Class1 Residual Solvents following USP 624
The chromatogram turned out clean and looking like it should, but I wanted to see if I could speed up the analysis. I used the new conditions below:
| Lucidity GC-FID Conditions | |||
|---|---|---|---|
| Carrier | Hydrogen | ||
| Control | Pressure | ||
| Flow | 2.0 mL/min | ||
| Split ratio | 10:1 | ||
| Column | Rtx-624 | 30 m x 0.25 mm, 1.40 um | |
| Injector | 280 ℃ | ||
| Incubation Temperature | 80 ℃ | ||
| Incubation Time | 45 min | ||
| Syringe Temperature | 150 ℃ | ||
| FID | 320 ℃ | ||
| Oven Program | |||
| Rate | Temperature | Hold Time | |
| 30 ℃ | 6 min | ||
| 15 ℃/min | 85 ℃ | 2 min | |
| 35 ℃/min | 250 ℃ | 0 min | |
Chromatogram of Residual Solvents using a faster method.
As you can see there was still good separation of the peaks with a much faster total run time, about 16 and a half minutes versus one hour. Whichever method you choose, the GC-FID can handle the analysis.
These methods show that the Lucidity GC-FID with PAL autosampler system is able to run Residual Solvents by Head Space injection. If you’d like more information or to request a demonstration of the Lucidity GC-FID with PAL autosampler click the link below!