A nitrate ion-selective electrode (NO3 --ISE) has been developed based on tetradodecylammonium bromide as an anion exchanger and 2-nitrophenyl octyl ether as a plasticizer. The NO3 -

A sequential injection analysis (SIA) system for the determination of SCN -ion using a microfluidic polymer chip with an embedded SCN -ion-selective electrode (SCN --ISE) as a detector was developed. Under the optimal flow conditions of the SIA system, the SCN --ISE showed a good linear relationship between peak heights and logarithmic concentrations of SCN -ion with a Nernstian slope of 59.4 ± 3.8 mV decade -1 in a concentration range from 1.0 × 10 -5 to 1.0 × 10 -1 mol dm -3 . Sample throughput of the present system for the determination of SCN -ion was approximately 12 samples h -1. The proposed SIA system was applied to the determination of the level of SCN -ion in human saliva samples.

A sequential injection analysis (SIA) system for the determination of NO 3 À ions using a microfluidic polymer chip with an embedded NO 3 À ion-selective electrode (NO 3 À -ISE) as a detector was developed.Under the optimal flow conditions of the SIA system, the NO 3 À -ISE showed a good linear relationship between peak heights and logarithmic concentrations of NO 3 À ions with a Nernstian slope of 57.1 mV per decade in a concentration range from 1.0 Â 10 À5 to 1.0 Â 10 À1 mol dm À3 . Sample throughput of the present system for the determination of NO 3 À ions was ca. 12 samples per h. The proposed SIA system was applied to the determination of the level of NO 3 À ions in environmental water samples, such as tap water, well water and river water. À-ISE, which we have developed as a detector,