I was trying to optimize method development of mercury analysis by extraction using SPME and detecting using GC-ECD. I plan to extract mercury analytes from seawater samples. i'm using sodium tetraphenylborate to derivatize analyte and the chromatogram of standard extraction are shown below. After searching and try to improve the possibilities causes of tailing peak e.g column type, end narrow of column, solvent and liner injection, the tailing peak was reduce but still not symmetrical peak. I would like to receive opinion from expertise, it is acceptable in this condition (Figure) and what possibilities to make symmetrical peak. if anyone have experience about this situation, hope can assist mine. Normally what LOD for mercury species if chromatographic separation using GC-ECD. Since i read book there mention LOD for mercury in biological sample is 1 ng/g = ppb. But my method detection limit so far below than ppb.
Dear Dr M. Farooq Wahab
Thank you for your enclosed file. Basically i have adjusting my oven program temperature starting from 100 - 300 C. Even try to figure out optimise flow rate, which determine 1.0 ml/min for flow rate and 4.0 ml/min for carrier gas make up. I think the same way when you mention about affinity, one of the aim to be solve this problem is reducing affinity of mercury on stationary phase but i have no idea and keep searching
I also try to added l-cysteine in extracted sample since it can assist mobilisation of analytes. But no improvement in term of reducing tailing peaks
Chromatogram above is standard injection of mixture Hg. So far i only try 2 column (DB-5Ms and non polar Hp-1). i also found one research paper those focussing on analysis mercury in fish tissue (http://www.agriculturejournals.cz/publicFiles/50287.pdf). I just worried it is acceptable in quantification if have tailing peak in standard analysis
Thank you so much for article link. Very useful for mine. i also will conduct particular test as you mention above :)
- Badges
- Science topic
- Similar topics
- Analytical Chemistry
- Extraction