a) Analysis of traces of glyphosate, (a nonpolar herbicide) in a tea drink sample was done using a solid phase extractio
Posted: Fri Jul 15, 2022 4:45 pm
a) Analysis of traces of glyphosate, (a nonpolar herbicide) in atea drink sample was done using a solid phase extraction (SPE)method prior to liquid chromatography analysis.
i) A C18 SPE cartridge gave efficient extraction compared to C1SPE sorbent for the above analysis. Explain. (3 marks)
ii) Explain why in the above SPE analysis, water was usuallyused in the elution of interferences step. (3 marks)
iii) Suggest a suitable solvent for the elution of glyphosate inthe analyte elution step. (1 mark)
iv) Explain why headspace solid phase microextraction (HS-SPME)was not a suitable approach in this analysis. (2 marks)
b) If you were to analyse a nonpolar compound in soil, whichsample preparation method is more suitable, supercritical fluidextraction (SFE) or Soxhlet extraction? Why and why not the otherone?
i) A C18 SPE cartridge gave efficient extraction compared to C1SPE sorbent for the above analysis. Explain. (3 marks)
ii) Explain why in the above SPE analysis, water was usuallyused in the elution of interferences step. (3 marks)
iii) Suggest a suitable solvent for the elution of glyphosate inthe analyte elution step. (1 mark)
iv) Explain why headspace solid phase microextraction (HS-SPME)was not a suitable approach in this analysis. (2 marks)
b) If you were to analyse a nonpolar compound in soil, whichsample preparation method is more suitable, supercritical fluidextraction (SFE) or Soxhlet extraction? Why and why not the otherone?