Coupling a bio-accumulator organism and MALDI-TOF MS: an early warning detection system for microcystins in water bodies

Abstract

Microcystins produced by freshwater cyanobacteria pose serious threats to human health and are a growing problem in drinking water supplies worldwide. Toxin detection and identification in water reservoirs when cyanobacterial density is still low is a key step to predict harmful algal blooms and to allow the safe use of the resource. For this purpose, developing sensitive and rapid methods of analysis is crucial. Adopting a strategy that couples the use of a filter-feeder organism (Unio elongatulus, Pfeiffer 1825 (Bivalvia: Unionidae)) with matrixassisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) technology, effective microcystin detection was achieved. The performances of MALDI-TOF MS, high-liquid-performance chromatography with diode array detector (HPLC-DAD) and enzyme-linked immunosorbent assays (ELISA) test were compared. The results obtained in this study suggest that the exploitation of an efficient bioaccumulator organism, coupled with a rapid and sensitive analytical method, can be a very useful strategy in monitoring programs for early and prompt risk management.

A Mini-Review on Detection Methods of Microcystins

“…MCs detection by HPLC depends on on-site sampling, sample processing and laboratory analysis which can be time demanding. Moreover, due to its low selectivity and time response, it is not suitable for rapid processing of multiple samples [ 75 , 77 , 94 , 100 , 129 ]. HPLC is also constrained by the large number of diverse MC variants and the commercial availability of standard compounds without which identification of MC becomes impossible.…”

“…Mass spectrometry novels including double-sided magnetic molecularly imprinted polymer modified graphene oxide (DS-MMIP@GO) based MSPE combined with LC-MS/MS (DS-MMIP@GO and LC–MS/MS), a new approach based on molecular networking analysis of LC-MS/MS, time-efficient LC-MS precursor ion screening method that facilitates MCs detection and identification, and immunocapture LC−MS/MS using an antibody that recognizes the Adda portion of MCs [ 26 , 73 , 75 , 122 ] have been established and validated for effective MCs identification. Besides, the developed paper spray ionization method coupled with a time of flight (TOF) MS and a filter-feeder organism coupled with matrix-assisted laser desorption ionization-TOF MS (MALDI-TOF MS) were found to yield effective MCs determination in various water samples [ 83 , 129 ]. It is worth knowing that the high throughput method based on on-line SPE coupled to LC–quadrupole TOF resolution MS (on-line SPE-LC-QToF HRMS) (LOD between 0.004 and 0.01 µg/L), on-line SPE-UHPLC-HRMS (LOD between 8 and 53 ng/L), online SPE-UHPLC-MS/MS (LOD between 0.1 and 0.5 µg/kg) and online concentration LC/MS/MS workflow (LOD between 0.6 and 3.8 ng/L) also successfully detected different variants of MC in water samples [ 34 , 96 , 101 , 102 ].…”

“…It is of interest that MS can be used to separate, quantify and present potential for high throughput towards MCs detection [ 101 , 102 , 103 , 122 ]. With the availability of suitable analytical standards, the technique can be used to confirm, identify and quantify variants of MC in an unknown sample, and regarding method specificity LC/TOF-MS is preferred due to its accurate mass capability [ 83 , 84 , 88 , 103 , 129 ]. This may provide the specificity and sensitivity needed to advise operational decisions for MC variants found in drinking water sources.…”

In situ use of bivalves and passive samplers to reveal water contamination by microcystins along a freshwater-marine continuum in France

“…These results are in line with previous findings demonstrating that Anodonta sp. ingest either colonial (i.e., Microcystis) or filamentous (i.e., Planktothrix) cyanobacteria, and subsequently accumulate MCs (Gkelis et al, 2006;Dionisio Pires et al, 2007;Barda et al, 2015;Bontes et al, 2016;Lauceri et al, 2017;Lepoutre et al, 2020). In this study, MC accumulation levels varied depending on which genus dominated the phytoplankton community.…”

Quantifying cryptic function loss during community disassembly

“…Otherwise, we extracted values from figures using the software PLOTDIGITIZER. As a result, we obtained 42 measurements from 11 studies (Baker & Hornbach, , ; Ferreira‐Rodríguez, Fernández, Cancela, & Pardo, ; Gatenby, ; Gatenby, Kreeger, Patterson, Marini, & Neves, ; Kryger & Riisgård, ; Lauceri et al, ; Liu, Xie, & Wu, ; Pusch, Siefert, & Walz, ; Vanden Byllaardt & Ackerman, ; Vanderploeg, Liebig, & Nalepa, ). Unit conversions were required for several studies and were detailed in Appendix .…”