Coccolithophore calcification studied by single-cell impedance cytometry: Towards single-cell PIC:POC measurements

TY - JOUR

T1 - Coccolithophore calcification studied by single-cell impedance cytometry: Towards single-cell PIC:POC measurements

AU - de Bruijn, Douwe S.

AU - ter Braak, Paul M.

AU - Van de Waal, Dedmer B.

AU - Olthuis, Wouter

AU - van den Berg, Albert

N1 - 7068, AqE; Data archiving: no NIOO data, no NIOO project

PY - 2021/2/1

Y1 - 2021/2/1

N2 - Since the industrial revolution 30% of the anthropogenic CO2 is absorbed by oceans, resulting in ocean acidification, which is a threat to calcifying algae. As a result, there has been profound interest in the study of calcifying algae, because of their important role in the global carbon cycle. The species studied, coccolithophore Emiliania huxleyi, is considered to be globally the single most dominant calcifying algae, which creates a unique exoskeleton from inorganic calcium carbonate platelets. The PIC (particulate inorganic carbon): POC (particulate organic carbon) ratio describes the relative amount of inorganic carbon in the algae and is a critical parameter in the ocean carbon cycle. In this research we explore the use of microfluidic single-cell impedance spectroscopy in the field of calcifying algae. Microfluidic impedance spectroscopy enables us to characterize single-cell electrical properties in a non-invasive and label-free way. We use the ratio of the impedance at high frequency vs. low frequency, known as opacity, to discriminate between calcified coccolithophores and coccolithophores with a calcite exoskeleton dissolved by acidification (decalcified). We have demonstrated that using opacity we can discriminate between calcified and decalcified coccolithophores with an accuracy of 94.1%. We have observed a correlation between the measured opacity and the cell height in the channel, which is supported by FEM simulations. The difference in cell density between calcified and decalcified cells can explain the difference in cell height and therefore the measured opacity.

AB - Since the industrial revolution 30% of the anthropogenic CO2 is absorbed by oceans, resulting in ocean acidification, which is a threat to calcifying algae. As a result, there has been profound interest in the study of calcifying algae, because of their important role in the global carbon cycle. The species studied, coccolithophore Emiliania huxleyi, is considered to be globally the single most dominant calcifying algae, which creates a unique exoskeleton from inorganic calcium carbonate platelets. The PIC (particulate inorganic carbon): POC (particulate organic carbon) ratio describes the relative amount of inorganic carbon in the algae and is a critical parameter in the ocean carbon cycle. In this research we explore the use of microfluidic single-cell impedance spectroscopy in the field of calcifying algae. Microfluidic impedance spectroscopy enables us to characterize single-cell electrical properties in a non-invasive and label-free way. We use the ratio of the impedance at high frequency vs. low frequency, known as opacity, to discriminate between calcified coccolithophores and coccolithophores with a calcite exoskeleton dissolved by acidification (decalcified). We have demonstrated that using opacity we can discriminate between calcified and decalcified coccolithophores with an accuracy of 94.1%. We have observed a correlation between the measured opacity and the cell height in the channel, which is supported by FEM simulations. The difference in cell density between calcified and decalcified cells can explain the difference in cell height and therefore the measured opacity.

KW - Flow cytometry

KW - Electrical impedance spectroscopy

KW - Single-cell characterization

KW - Algae

KW - Calcification

KW - national

KW - Plan_S-Compliant-TA

U2 - 10.1016/j.bios.2020.112808

DO - 10.1016/j.bios.2020.112808

M3 - Article

SN - 0956-5663

VL - 173

JO - Biosensors and Bioelectronics

JF - Biosensors and Bioelectronics

M1 - 112808

ER -