Determination of microcystins in algal bloom samples by ultra performance liquid chromatography-tandem mass spectrometry and elimination of their matrix effects

: A rapid and simple method was commonly used for the determination of microcystins by ultra performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). The reliability, accuracy and sensitivity of LC-MS/MS determination were affected by the matrix effect because of the complex matrices in algal bloom samples. In this study, the matrix interference and matrix effect problems were effectively reduced or eliminated by diluting samples, optimizing gradient elution programs, and reducing injection volumes. The correlation coefficients (r2) of the seven microcystins were ≥ 0.99. The limits of detection and limits of quantification ranged from 0.064 μ g/L to 0.103 μ g/L and 0.213 μ g/L to 0.343 μ g/L, respectively. Algal bloom samples were determined by diluting 10 times and injecting 5 μ L of sample volume. The method provides some references for the determination of microcystins. It is of great significance for ensuring the safety of drinking water source.