Polymeric membrane ion-selective electrodes (ISEs) have become attractive tools for trace-level environmental and biological measurements. However, applications of such ISEs are often limited to measurements with low levels of electrolyte background. This paper describes an asymmetric membrane rotating ISE configuration for trace-level potentiometric detection with a high-interfering background...

Nitrate-sensing system that consists of a micromachined sensor substrate, nitrate-permeable membrane, integrated microfluidic channels, and standard fluidic connectors has been designed, fabricated, assembled, and tested. Our microsensor was designed for in-situ monitoring of nitrate concentrations in ground water. A silver electrode was patterned for amperometric nitrate detection. An electroc...

Enzyme sensors based on the measurement of pH consist basically of a pH-sensitive electrode to which an enzyme-loaded membrane is attached. The conversion of substrate in the immobilized enzyme membrane results in a local change in pH which can then be measured. The pH-sensitive electrode used is usually a glass membrane electrode or an ISFET. In 1980, Caras and Janata [l] described the first I...

The construction, performance characteristics, and application of a novel polymeric membrane coated on a graphite electrode with unique selectivity towards SCN- are reported. The electrode was prepared by incorporating Ni(II)-2,2,4,9,9,11-hexamethyltetraazacyclotetradecanediene perchlorate into a plasticized poly(vinyl chloride) membrane. The influences of membrane composition, pH and foreign i...

thin film phthalocyanines(pc), incloding zinc, iron, and magnesium phthalocyani-nes, were prepared by vacuum deposition method. chronocoulometry was used to study the charge transfer reaction mechanism of ionic species through the thin films. the results obtained in chronocoulometric studies shows that the thin film phthalocyanines could operate via two mechanisms.the first mechanism metal pc t...

A comparison between several immobilization materials of AChE on surface of glassy carbon electrode(GCE) was presented. The immobilization methods employed crosslinking method with glutaraldehyde as a cross-linking agent and bovine serum albumin(BSA) as a protectant, AChE was immobilized on different membranes including nylon membrane, cellulose nitrate membrane and chitosan membrane respective...