Linearity, detection limit, quantification limit, accuracy and precision
were evaluated following the procedures described by the
International Conference on Harmonisation (ICH, 2005) using an
Ultraviolet–visible spectrophotometer (PG Instruments, T70+)
operating with 1 nm spectral bandwidth, ±0.3 nm wavelength
accuracy and a splitbeam optical system. This equipment was used
in all experiments unless otherwise stated.