Polargraphy Determination of Tetracycline in Environmental Water

A method for determination of tetracycline (TC) by polargraphy was proposed, which was based on the sensitization effect of cetyl trimethyl ammonium bromide (CTMAB) on the polarographic peak of TC. The optimized experimental conditions were as follows:① a mixture of CTMAB and Na₂HPO₄-NaH₂PO₄ buffer solution (pH 7.7) was used as the base solution; ② the scanning rate was 0.7 V·s^-1; ③ the starting potential was -0.85 V; ④ the stationary time was 6 s; ⑤ the temperature was 25-30℃. In above experimental conditions, linearity ranges for mass concentration of TC found were 0.02-1.0 mg·L^-1 and 1.0-80 mg·L^-1. Values of detection limit (3s/k) found was 0.001 5 mg·L^-1, and values of RSDs (n=6) found were both less than 4.0%. Test for recovery was made by standard addition method at 3 concentration levels, giving results in the range of 92.0%-120%.