Abstract:

A fast method for vanadium determination by ultrasound-assisted digestion-graphite furnace atomic absorption
spectrometry (UAD-GFAAS) was proposed. Using single factor and L9 (34) orthogonal array designs, the best digestion
conditions (30 min, 60 ℃) influencing and the best GFAAS conditions (ashing at 900 ℃ for 20 s, atomization at 2 700 ℃
for 5 s) were achieved. The UAD-GFAAS method could provide complete mineralization of the samples for vanadium
determination in sea cucumber with a detection limit of 1.44 × 10-3 μg/mL and acceptable analytical recovery of 94.2%–
105.4% for vanadium. Values of 0.27–1.43 μg/g in terms of total vanadium and 0.22–1.08 μg/g in terms of organic
vanadium were obtained in sea cucumbers from different sampling sites, suggesting a significant difference between North
and South coastal habitats of China. The highest vanadium content (2.56 μg/g) in Holothuria scabra was determined among
fourteen species of edible sea cucumber. Total vanadium and organic vanadium contents showed significant differences
among different species and different sampling sites of sea cucumbers. Moreover, most vanadium exists in an organic form.
Therefore, ultrasound-assisted digestion-graphite furnace atomic absorption spectrometry is a rapid, accurate and stable
method, which has a high practical value.

Key words: vanadium, sea cucumber, organic degree, ultrasound-assisted digestion and graphite furnace atomic absorption spectrometry