TY - JOUR

T1 - An optimized method for extraction and purification of inorganic phosphate from plant material for oxygen isotope ratio analysis

AU - Rieckmann, Maria Monrad

AU - Blake, Ruth Elaine

AU - Chang, Sae Jung

AU - Laursen, Kristian Holst

N1 - Publisher Copyright: © 2024 The Authors

PY - 2024

Y1 - 2024

N2 - Compound-specific stable isotope ratio analysis of oxygen isotopes in inorganic phosphate can be used to study biological phosphorus cycling and the transformation processes controlling the fate of phosphorus. However, methods for extraction of inorganic phosphate from plant tissue for oxygen isotope ratio analysis are not consistent. Further, the purification into solid silver phosphate can be challenging and laborious. In this work, a detailed and optimized method to provide a more consistent, easily implementable and reproducible extraction using trichloroacetic acid and subsequent purification of inorganic phosphate from plant material for oxygen isotope ratio analysis is presented. Key focus points were: uniform extraction of inorganic phosphate from barley leaves, removal of dissolved organic material, flexibility in regards to the amount of inorganic phosphate extracted for the purification into silver phosphate, reduced use of chemicals and, removal of co-precipitated oxygen-bearing compounds before analysis. Most notable optimizations to the method and associated effects were: • Drying of plant material before inorganic phosphate extraction increases the method applicability to a broader range of plant sample types. • Removal of dissolved organic matter improves inorganic phosphate purification. • Sample volume adjustment according to inorganic phosphate content is vital for effective and quantitative precipitations.

AB - Compound-specific stable isotope ratio analysis of oxygen isotopes in inorganic phosphate can be used to study biological phosphorus cycling and the transformation processes controlling the fate of phosphorus. However, methods for extraction of inorganic phosphate from plant tissue for oxygen isotope ratio analysis are not consistent. Further, the purification into solid silver phosphate can be challenging and laborious. In this work, a detailed and optimized method to provide a more consistent, easily implementable and reproducible extraction using trichloroacetic acid and subsequent purification of inorganic phosphate from plant material for oxygen isotope ratio analysis is presented. Key focus points were: uniform extraction of inorganic phosphate from barley leaves, removal of dissolved organic material, flexibility in regards to the amount of inorganic phosphate extracted for the purification into silver phosphate, reduced use of chemicals and, removal of co-precipitated oxygen-bearing compounds before analysis. Most notable optimizations to the method and associated effects were: • Drying of plant material before inorganic phosphate extraction increases the method applicability to a broader range of plant sample types. • Removal of dissolved organic matter improves inorganic phosphate purification. • Sample volume adjustment according to inorganic phosphate content is vital for effective and quantitative precipitations.

KW - Compound-specific

KW - Oxygen

KW - Phosphate

KW - Phosphorus

KW - Plants

KW - Stable isotopes

U2 - 10.1016/j.mex.2023.102541

DO - 10.1016/j.mex.2023.102541

M3 - Journal article

C2 - 38287963

AN - SCOPUS:85182385353

VL - 12

JO - MethodsX

JF - MethodsX

SN - 2215-0161

M1 - 102541

ER -