Page 180 - Analytical method for food addtives

E249–50: Nitrites 121

Reference 15,16 17 18

Detection UV at 205 nm UV at 210 nm. DAD 205–300 nm Coulometric, oxidation potential mV 700

Aqueous buffered acetonitrile at pH 6.5, flow rate 1.0 mL/min, injection volume 100 µL mM NaH 2 PO 4 at pH 7 isocratic, flow rate 1.0 mL/min, injection volume mM phthalic acid–10 % acetone (pH 5.0), flow-rate 1.0 mL/min, injection volume 20 µL

Mobile phase mM NaCl with 1 20 20–100 µL 2

Anion exchange, 4.6 mm, 10 µm; IC-PAK A HC (high capacity) – Waters Anion exchange IC anion PRP-X100 mm, column (125 × 4

Column × 150 column 5 µm)

Sample preparation/extraction Extracted from test sample with hot water. Treated with acetonitrile, filtered Deproteinised with acetonitrile, lyophilised and reconstituted in buffer Addition of borax to pH 8.6. Hot water extraction, cleaned and filtered

vegetables and baby foods Human plasma

Matrix Meat, and urine Spinach = suphanilamide = sulphamethizole = sulphadimidine

Method HPLC/IC
(b) IC IC Key: SAM SM SD