Physical and Theoretical Chemistry Laboratory, Department of Chemistry, University of Oxford, South Parks Road, Oxford, UK.
Department of Earth Sciences, University of Oxford, South Parks Road, Oxford, UK.
Angew Chem Int Ed Engl. 2021 Sep 13;60(38):20999-21006. doi: 10.1002/anie.202108435. Epub 2021 Aug 15.
Coccoliths are plates of biogenic calcium carbonate secreted by calcifying marine phytoplankton; annually these phytoplankton are responsible for exporting >1 billion tonnes (10 g) of calcite to the deep ocean. Rapid and reliable methods for assessing the degree of calcification are technically challenging because the coccoliths are micron sized and contain picograms (pg) of calcite. Here we pioneer an opto-eletrochemical acid titration of individual coccoliths which allows 3D reconstruction of each individual coccolith via in situ optical imaging enabling direct inference of the coccolith mass. Coccolith mass ranging from 2 to 400 pg are reported herein, evidencing both inter- and intra-species variation over four different species. We foresee this scientific breakthrough, which is independent of knowledge regarding the species and calibration-free, will allow continuous monitoring and reporting of the degree of coccolith calcification in the changing marine environment.
球石是由钙化海洋浮游植物分泌的生物成因碳酸钙板；这些浮游植物每年负责将超过 10 亿吨（10 克）方解石输送到深海。评估钙化程度的快速可靠方法在技术上具有挑战性，因为球石的尺寸为微米级，并且含有皮克（pg）级的方解石。在这里，我们开创了一种单个球石的光电化学酸滴定法，该方法允许通过原位光学成像对每个单个球石进行 3D 重建，从而可以直接推断出球石的质量。本文报告了 2 到 400 皮克的球石质量，证明了四个不同物种之间存在种间和种内变异。我们预计，这一独立于物种知识且无需校准的科学突破，将能够持续监测和报告海洋环境变化中球石钙化的程度。
