[Determination of five microcystins in drinking water by HPLC/MS/MS]

Area of Science:

• Environmental Chemistry
• Analytical Chemistry

Context:

• Microcystins are potent cyanotoxins that contaminate water sources, posing significant risks to public health.
• Accurate and sensitive detection methods are crucial for monitoring microcystin levels in drinking and source water.

Purpose:

• To establish and validate a high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) method for quantifying five common microcystins (MC-LR, MC-LW, MC-RR, MC-LF, MC-YR).
• To assess the method's performance characteristics, including linearity, detection limits, accuracy, and precision.

Summary:

• The developed HPLC-MS/MS method utilizes electrospray ionization in positive mode with multiple reaction monitoring for sensitive detection.
• Excellent linearity was observed for the five microcystins (correlation coefficients 0.9994-1.0000) within the 0.5-50 µg/L range.
• The method demonstrated low detection limits (0.06-0.08 µg/L), high recoveries (91.2%-102%), and good precision (RSDs 2.11%-3.26%).

Impact:

• The validated HPLC-MS/MS method is convenient, accurate, and exhibits minimal interference, meeting national health standard requirements for microcystin determination.
• This method provides a reliable tool for public health agencies and researchers to ensure the safety of drinking water and monitor environmental water quality.