Results obtained with a potentiometric analyzer, NOVA 1, specific for sodium and potassium, were compared with those by flame photometry. Both instruments showed linearity within a physiological range of sodium and potassium concentrations and had similar precisions. Volume displacements from addition of albumin or Intralipid to aqueous samples yielded the predicted lower flame-photometric resu...

A novel triiodide ion-selective electrode based on a clotrimazole-triiodide ion pair as a membrane carrier was prepared. It has a linear response to triiodide from 8 x 10(-6) to 5 x 10(-3) M with a slope of -68.9 mV per decade and a detection limit of 5 x 10(-6) M. The electrode response is independent of the pH of the solution in the pH range 2-9. It has a very short response time and can be u...

A potentiometric aptasensing assay that couples the DNA nanostructure-modified magnetic beads with a solid-contact polycation-sensitive membrane electrode for the detection of Vibrio alginolyticus is herein described. The DNA nanostructure-modified magnetic beads are used for amplification of the potential response and elimination of the interfering effect from a complex sample matrix. The soli...

The fabrication and application of an intracellular K + -selective microelectrode is demonstrated. ZnO nanowires with a diameter of 100–180 nm and a length of approximately 1.5 μm are grown on a borosilicate glass microcapillary. The ZnO nanowires were coated by a K + -ionophore-containing membrane. The K + -selective microelectrode exhibited a K + -dependent potentiometric response versus an A...

We report here on an electrogenerated chemiluminescence (ECL) readout for potentiometric ion-sensors, thereby offering an optical sensor output without the need for a reference ion (typically the hydrogen ion) that inconveniences ionophore based optical sensor principles. The compartment for ECL generation is physically separated from the sample by a bridge, and no current flows through the sam...

Transient network hydrogels cross-linked through histidine-divalent cation coordination bonds were studied by conventional rheologic methods using histidine-modified star poly(ethylene glycol) (PEG) polymers. These materials were inspired by the mussel, which is thought to use histidine-metal coordination bonds to impart self-healing properties in the mussel byssal thread. Hydrogel viscoelastic...

An enzyme-metal-insulator-silicon (EMIS) structured chemical sensor based on photovoltage technology is constructed for potentiometric biosensing of glucose in a flow-injection analysis (FIA) system. To enhance the sensibility of the sensor to glucose, an ultra-thin (60 nm) film of polypyrrole (PPy)-glucose oxidase (GOD) is formed as the glucose-sensitive membrane through a simple electropolyme...

The construction and general performance characteristics of three piezoelectric quartz crystal sensors responsive to the pentoxyverine are described here. This kind of non-potentiometric sensing method is based on use of ion-pair complexes of the pentoxyverine cation with three counter anions, namely, tungstophosphate, tetraphenylborate and picrolonate. The complexes were embedded in a PVC matr...

The interest in nuclear safeguards is constantly growing, as more nuclear programs are being exposed all over the world. In this work, a simple, rapid and reliable method has been applied for the determination of uranium content in aqueous media based on using potentiometric sensor. The developed tool was found to be capable of verifying the operator declarations in a wide concentration range w...

The aim of the present work was to study a simple colorimetric and potentiometric biosensor based on urease inhibition by Pb (II) ions for its estimation in milk samples. Urease immobilized on nylon membrane by hydrosol gel method was used as the biocomponent to demonstrate the metal effect on the enzyme activity using phenol red as the pH indicator. A lower limit detection of 38.6μm was achiev...