Table 1 Summary of analytical methods, their advantages and limits used for the determination of total phosphorus in plants
Method | Advantages | Disadvantages |
|---|---|---|
Colorimetric assays | ||
Molybdenum blue method | Higher range of linear response (up to ~ 13 μm Pi) than malachite green assay (up to ~ 6 μm Pi) Automation possible | Complete destruction of the sample Discrimination between the different pools of phosphate (e.g. orthophosphate, hydrogen phosphate) impossible |
Malachite green method | Easy to implement Stability of reagents Five times more sensitive than the molybdenum blue method - downscaling possible (range of detection 0.3 to 8 ng of Pi) | |
ICP-AES and ICP-MS | Quantification of P and other elements in a single analysis | Complete destruction of the sample Discrimination between various P-metabolites impossible |
FAAS/ HR-CS FAAS | Low operational costs Good analytical performance HR-CS FAAS improves sensitivity and detectability | Complete destruction of the sample Limited sensitivity, its capability to only measure one element at a time and limited linearity |
HR-CS ETAAS | High sample throughput, good sensitivity, sufficient precision, and straightforward calibration with aqueous standards | Complete destruction of the sample Single-element analysis |
X-ray spectrometry (XRF) | High sensitivity Compatible with measurements at ambient temperature and pressure | Relative quantification Discrimination between various P-metabolites impossible Difficult sample preparation |
Secondary Ion Mass Spectrometry (SIMS) | High sensitivity P imaging in the different compartments of the cell Possibility to colocalize P with other elements Discrimination between isotopes | Relative quantification Discrimination between various P-metabolites impossible Difficult sample preparation |