Large volume sample stacking of cationic tetracycline antibiotics toward 10 ppb level analysis by capillary electrophoresis with UV detection.

This paper aimed to build up a sensitive CE method for the analysis of tetracyclines (TCs) antibiotics (including tetracycline, chlorotetracycline, oxytetracycline, and doxycycline) with conventional UV detection. Here, the large volume sample stacking was applied to achieve in capillary preconcentration of the targets. To achieve large volume sample stacking, the essential step was a large volume of sample (around 83.

Determination of trace amounts of boron in steels by on-line reaction/concentration/separation using an anion-exchange column.

A method for the on-line absorptiometric determination of trace amounts of boron in steels was developed using an anion-exchange column presorbed with chromotropic acid. The on-line reaction and separation were achieved by controlling the pH in order to accelerate the complex formation in the column by 2.7 and to stabilize the complex at pH 8 for the selective elution of a 1:2 complex and its detection at 350 nm.

Anion exchanger as a reaction/separation medium-absorptiometric determination of trace amounts of boron in waters by on-line complexation with chromotropic acid presorbed on the anion-exchange column.

A novel method of on-line absorptiometric determination for trace amounts of boron was developed based on the complexation with chromotropic acid presorbed on an anion-exchange column. On-line reaction and separation were achieved by controlling pH conditions in solutions to accelerate the 1:2 complex formation in the concentration process at pH 3 and to stabilize the complex in the separation process at pH 8. About 75% of the boron introduced into the stream was kinetically collected as the 1:2 complex on the column under the experimental conditions.