Quantitative Determination of Microcystins in Rat Plasma by LC–ESI Tandem MS

Abstract

A rapid and sensitive method was developed and validated for the determination of MCYST (microcystin)-RR, -LR, and [Dha 7 ] MCYST-LR in rat plasma by liquid chromatography-tandem mass spectrometry. The analytes were extracted from rat plasma by protein precipitation, followed by solid-phase extraction. Liquid chromatography with electrospray ionization mass spectrometry, operating in selected reaction monitoring (SRM) mode, was used to quantify MCYST-RR, -LR, and [Dha 7 ] MCYST-LR in rat plasma. The recoveries for each analyte in rat plasma ranged from 70.8 to 88.7%. The calibration curve was linear within the range from 0.005 to 1.25 lg mL ] MCYST-LR. The overall precision was determined on three different days. The values for within-and between-day precision in rat plasma were within 15%. This method was applied to the identification and quantification of microcystins in rat plasma with acute exposure of microcystins via intravenous injection.

Simultaneous quantification of microcystins and nodularin in aerosol samples using high‐performance liquid chromatography/negative electrospray ionization tandem mass spectrometry

“…We obtained LOD values ranging between 1 fg/μL (MC LW, MC LF) and 9 fg/μL (MC YR). The literature reports LODs ranging between pg/μL and ng/μL . Our observed instrumental detection limits are similar to the best LOD values reported in the literature using ESI(+)‐MS/MS, proving that our method is a valid alternative.…”

“…We developed a chromatographic separation using alkaline conditions, resulting in high‐resolution separation. The LODs for all toxins were determined between 1 and 9 fg/μL, which are similar to or lower than those reported in the iterature, while the MDLs ranged between 23 and 164 pg absolute amount. As no available cyanotoxin certified reference atmospheric materials exist, we validated the method by spiking five clean fibre filters.…”

“…Reversed‐phase HPLC coupled with photodiode array UV detection (DAD) has been used to identify a variety of MCs, even if is recognised that mass spectrometry detection is more specific and sensitive . Modern LC/MS protocols for quantitative analysis are usually based on the reversed‐phase separation coupled through an electrospray ionization (ESI) source to a single or triple quadrupole MS instrument, obtaining pg per injection values as typical detection limits . The aim of this study was to develop a new sensitive method to simultaneously quantify seven cyanobacterial toxins (microcystin LA, LR, LF, LW, LY, YR and nodularin) in the aerosol samples.…”

“…Little research exists on these toxins in the atmospheric environment. [5,6] In response to the need to monitor water sources relative to the proposed World Health Organization (WHO) drinking water guidelines, many techniques were developed to detect and quantify cyanobacterial toxins in water [7][8][9][10][11][12][13] and other matrices such as tissue, [9,[14][15][16] plasma, [17] or sediment. [18] Only a few studies in the literature [5,6] report the investigation of cyanotoxins in aerosol samples, and even less is known regarding aerosol contamination and human exposure.…”

Quantitative liquid chromatography–tandem mass spectrometry method for determination of microcystin-RR and its glutathione and cysteine conjugates in fish plasma and bile

“…most widely used as extraction solvent in biological fluid samples [2,[28][29][30]. In the plasma preparation, methanol was chosen for further development as it had better recoveries (93.7%, 91.1% and 85.8% for MC-RR, MC-RR-GSH and MC-RR-Cys, respectively), which were obviously higher than those of acetonitrile (78.6%, 75.0% and 78.2%) and EDTA-Na 2 (0.01 M)-5% acetic acid (35.6%, 32.9% and 32.8%).…”