Spectrophotometer parameters (Varian AAS 240 FS, USA)

Wavelength

193.7

Exit slit

0.7 nm

Ultra-lamp intensity

10 mA

Signal measurement mode

pic high

Linearity

2.5 - 15.0 ppb (r² = 0.99)

Precision (n = 3)

5.6%

LOQ

2.5 ppb

LOD

0.5 ppb

NaBH₄ concentration

0.6 % (m/v) stabilised with NaOH (0.5%)

NaBH₄ flow rate

4 - 6 mL/min

HCl concentration

5 M

HCl flow rate

9 - 11 mL/min

Argon flow rate

40 - 60 mL/min