Methods | Limit of detection | Reference |
HPLC-UV (derivatization with difluoroborane) | Absolute amount of 0.040 ng | [6] |
Capillary zone electrophoresis- diode array detector | Not described absolute amount; 0.034 μg/mL as concentration | [7] |
HPLC-UV (no derivatization, i.e. direct injection) | Absolute amount of 1 ng (at 240 nm); 0.005 μg/mL as concentration |
|
Absolute amount of 2 ng (at 345 nm); 0.01 μg/mL as concentration | [8] | |
HPLC-UV (derivatization with NBD-F) | Absolute amount of 0.33 ng; 0.05 μg/mL as concentration | [9] |
HPLC-VIS (derivatization with Dabsyl-Cl) | Absolute amount of 0.26 ng; 0.18 μg/mL as concentration | This paper |