Analysis of Pharmaceutical Active Compounds in Complex Water Samples: Sample Filtration as an Option.

Area of Science:

• Environmental Chemistry
• Analytical Chemistry

Background:

• Sample pretreatment is crucial for chromatographic analysis success, especially in complex matrices like wastewater.
• Pharmaceutical active compounds (PhACs) analysis often involves solid-phase extraction (SPE) and UPLC-MS/MS.
• Wastewater's high organic matter necessitates filtration to prevent SPE cartridge clogging and improve efficiency.

Purpose of the Study:

• To determine the optimal pretreatment method for quantifying PhACs in wastewater and surface waters.
• To assess if filtering water samples prior to SPE impacts PhAC recovery.
• To investigate correlations between PhAC concentrations, turbidity (TUR), and permanganate index (PI).

Main Methods:

• Analysis of 26 PhACs in filtered and unfiltered water samples.
• Filtration using paper, 1 µm glass microfiber, and 0.45 µm Nylon filters.
• Determination of turbidity (TUR) and permanganate index (PI) to assess organic matter content.

Main Results:

• No significant differences were observed in PhAC quantification between filtered and unfiltered wastewater samples.
• PhAC concentrations showed a positive correlation with turbidity (TUR) and a negative correlation with permanganate index (PI) for most analytes.
• Filtration did not lead to the elimination of target PhACs, suggesting it is a safe step.

Conclusions:

• Pre-filtering wastewater samples does not significantly affect the quantification of pharmaceutical active compounds (PhACs).
• The filtration step is effective in preventing SPE cartridge clogging without compromising analytical results.
• The findings support direct SPE without pre-filtration as a viable and potentially more efficient method for PhAC analysis in wastewater.