What steps do I need to take before injecting it to the LC-MS for wastewater SPE extracted samples?

Yerabham Praveenkumarreddy @Yerabham-Praveenkumarreddy

29 June 2020 0 8K Report

Solid-phase extracted (Oasis HLB cartridge) wastewater samples were preserved in methanol for HPLC-MS-MS analysis at -20°C. After a lapse of 3 months, I see some of the extracted samples show turbidity/flocculation. What could be the reason? Further, what steps do I need to take (for eg. filtration) before injecting it to the LC-MS?

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