in order to study the cu(ii) ion selective electrode, an optimized membrane was prepared by mixing of 30 mg of pvc powdered, 5 mg of considered ionophore, 60 mg of plasticizer and 5 mg of additive. the sensor showed a near nernstian response for cu(ii) ions over a concentration range from 1.0×0-6 –1.0×0-2 m with a slope of 28.90.5 mv per concentration decade with a working ph range of 3.5-6.3. ...

a new polyvinyl choloride (pvc) membrane sensor for cerium (iii) was prepared based on 4,13-didecyl-1,7,10,16-tetraoxa-4,13-diazacyclooctadecane (kryptofix22dd) as an ionophore. the sensor exhibites a linear concentration range of 1.0×10-6to 1.0×10-1m, with a nernstian slope of 18.0±1.0 mv/decade, and a detection limit of 9.7×10-7m. it has a fast response time (5 s) and can be used for two mont...

The protonation constants of new group of peptidomimetic cyclophanes with valine or phenylalanine moieties incorporated into the macrocyclic skeleton as well as their linear analogues were determined by potentiometric measurements in solutions of methanol-water mixtures at 25°C and constant ionic strength. The influence of cavity size, location of protonation sites, and attached substituents of...

In this work, a novel Zr02+ PVC-based membrane sensor based on 4,7,13,16,21,24-hexa oxa-1,10- diazabicyclo[8,8,8]- hexa cosane (HODBHC) as a new ionophore is presented. The sensor displays a linear dynamic rangebetween 1.0x 10-1 and 1.0x10 6 M, with a near Nernstian slope of 29.9 ± 0.4 mV per decade in an acidic solution(pH=1). The limit of detection is 8.0 x 1 0 7 M. The electrodes possess adv...

In order to preparing strontium ion selective electrode 6-(4- nitropheny1)-2-pheny14, 4- dipropy1-3, 5-diaza-bicyclo [3, 1, 0] hex-2-ene (NPDBH) was used as an ionophore. This electrode responds to Sr (II)ion with a sensitivity of 28.2 ± 0.5 mV/decade over the range 1.0 x 10-6 to 1.0 Mat pH 3.0-10.0. Thelimit of detection was 2.4 x 10-7 M. The influences of membrane composition, the pH of the t...

COVID-19, a viral respiratory illness, is caused by Severe Acute Respiratory Syndrome Corona Virus 2 (SARS-CoV-2), which was first identified in Wuhan, China, 2019 and rapidly spread worldwide. Testing isolation were essential to control the virus’s transmission due severity of disease. In this context, there global interest feasibility employing nano-biosensors, especially those using graphene...

Sodium was determined by flame photometry and by direct potentiometry in 56 serum or plasma samples from 24 patients with multiple myeloma or macroglobulinemia. We observed differences between the two techniques as large as 17 mmol/L (12%). The flame-photometric values decreased relative to the direct-potentiometric values as protein increased or water content decreased. Moreover, the two sodiu...

   Significant effects of magnetic iron oxide (Fe3O4) nanoparticles on the potentiometric behavior of carbon paste electrode for bio determination of Isoniazid aromatic drug (INH) were studied. The electrochemical performance of modified Fe3O4/CPE was investigated. The constructed Fe3O4/CPE showed high precision, sensitivity ...

A new polyvinyl choloride (PVC) membrane sensor for cerium (III) was prepared based on 4,13-didecyl-1,7,10,16-tetraoxa-4,13-diazacyclooctadecane (kryptofix22DD) as an ionophore. The sensor exhibites a linear concentration range of 1.0×10-6 to 1.0×10-1 M, with a Nernstian slope of 18.0±1.0 mV/decade, and a detection limit of 9.7×10-7 M. It has a fast response time (5 s) and can be used for two m...

A new polyvinyl choloride (PVC) membrane sensor for cerium(III) was prepared based on 4,13-didecyl-1,7,10,16-tetraoxa-4,13-diazacyclooctadecane (kryptofix22DD) as an ionophore. The sensorexhibites a linear concentration range of 1.0×10-6 to 1.0×10-1 M, with aNernstian slope of 18.0±1.0 mV/decade, and a detection limit of 9.7×10-7M. It has a fast response time (5 s) and can be used for two month...