Label-free detections of biomolecules have attracted great attention in a lot of life science fields such as genomics, clinical diagnosis and practical pharmacy. In this article, we reviewed amperometric and potentiometric biosensors based on carbon nanotubes (CNTs). In amperometric detections, CNT-modified electrodes were used as working electrodes to significantly enhance electroactive surfac...

The unique potentiometric response of mercury sensors was investigated in aqueous Cl(-)-rich media, which are often encountered in natural, especially biological samples. The conventional neutral-carrier-based Hg(II)-ISEs are not practically useful because the Cl(-) concentrations in natural aqueous samples are normally too high for mercury to be present in the form of Hg(2+). Negative potentio...

The simplest transducer in the development of potentiometric biosensors is the glass pH electrode. Glucose oxidase immobilization was achieved using cellophane [1], nylon [1-6] or nitrocellulose [5,7] membranes that are subsequently fixed on the sensitive bulb of the pH electrode that senses the pH diminution, as a result of the biocatalytical reaction occurring in the enzyme layer (glucose oxi...

Based on international standard procedures, the degree of unsaturation on biodiesel was evaluated, called iodine value. Two titration techniques were used to determine the iodine value: colorimetric and potentiometric techniques. The uncertainty of measurement was used to evaluate the quality of the results. The potentiometric technique showed better quality in the determination of the iodine v...

All-solid-state sensors with polyvinyl chloride (PVC)-based membranes using off-the-shelf N-hydroxysuccinimide (NHS) and succinimide (Succ) ionophores were prepared using DOP (dioctyl phthalate) and NPOE (ortho-nitrophenyloctyl ether) as plasticizers. Good responses were obtained when NHS was used. The potentiometric response of the proposed electrode is independent of pH over the range 2-6. Th...

A new nucleic acid-based magnetic potentiometric aptasensing platform was designed for in situ amplified measurement of prostate-specific antigen with the catalytic hairpin assembly.

A first step towards a microfabricated potentiometric thin-film sensor array for the simultaneous detection of Pb, Cd and Cu has been realized. The sensitive layers used are on the basis of chalcogenide glass materials. These thin-film chalcogenide glass materials that consist of mixtures of Pb-Ag-As-I-S, Cd-Ag-As-I-S or Cu-Ag-As-Se have been prepared by pulsed laser deposition technique. The d...

A laboratory computer controlled potentiometric titrator interfaced to a diode array spectrophotometer is described. The titrator consists of widely used, commercially available components; therefore, major attention is given to modes of interconnection and software implementation in data format and system control. Replicate potentiometric titrations of glycines gave a relative standard deviati...