Fluoro-electrochemical microscopy reveals group specific differential susceptibility of phytoplankton towards oxidative damage

Abstract

In the vicinity of an electrode creating a highly oxidising environment the fluorescence – arising from the presence of chlorophyll-a – of single cellular phytoplankton becomes inhibited.

The oxygen reduction reaction at silver electrodes in high chloride media and the implications for silver nanoparticle toxicity

“…36–38 The ˙OH radical, with a reduction potential reported at 2.31 V, 39 is a strongly oxidizing reagent and can kill a diverse range of single-cellular phytoplankton at a near-mass-transport limited rate. 40 ˙ON + O 2 − ˙ → ONOO − H 2 O 2 + O 2 − ˙ → O 2 + ˙OH + OH − …”

Opto‐Electrochemical Dissolution Reveals Coccolith Calcium Carbonate Content

“…In the following, a suspension of detached coccoliths is placed in an opto‐electrochemical cell [19] which allows the generation of a tiny amount of acid local to some of the coccoliths as shown in the schematic in Figure 2. The resulting controlled dissolution of coccoliths is monitored optically, allowing their size to be measured as the dissolution proceeds to complete “titration” of the calcium carbonate content.…”

Single-entity coccolithophore electrochemistry shows size is no guide to the degree of calcification

“…More recently, proof-of-concept electrochemical methods have shown their ability to identify, in combination with fluorescence spectroscopy, the speciation of marine phytoplankton and, 32 separately, single-entity measurement of detached coccolith CaCO 3 masses. 22 In the present study, electrochemistry is utilised to provide a high-throughput single-entity PIC content measurement of living coccolithophores.…”