A DNA/chitosan-Fe₃O₄ magnetic nanoparticle bio-complex film was constructed for the immobilization of horseradish peroxidase (HRP) on a glassy carbon electrode. HRP was simply mixed with DNA, chitosan and Fe₃O₄ nanoparticles, and then applied to the electrode surface to form an enzyme-incorporated polyion complex film. Scanning electron microscopy (SEM) was used to study the surface features of...

New electrochemical technique with a Pt-Ag twin electrode is proposed for the determining the contents of iron sulfides (FeS and FeS(2)) in a suspension. After electrolytic oxidation with a Pt electrode, Fe(2+) was measured by linear sweep voltammetry. From relations of the charge amount from the baseline to the peak in the voltammogram of Fe(2+) with the content of FeS or FeS(2), linear calibr...

Electrochemical CO2 reduction provides a promising route to the sustainable generation of valuable chemicals and fuels. Tandem catalysts enable sequential CO2-to-CO CO-to-multicarbon (C2+) product conversions on complementary active sites, produce high C2+ Faradaic efficiency (FE). Unfortunately, previous tandem exhibit poor management CO intermediates, which diminishes FE. Here, we design segm...

a pvc-based membrane containing cerium phosphate was developed. unlike the cerium phosphate itself that acts as a cation exchanger, the membrane exhibited anion-exchange properties. therefore, the utility of this compound as a sensory element for detection of molybdate ions was pursued. the response of molybdate selective electrode based on this membrane was perfectly linear in the concentratio...

a pvc ion-selective membrane electrode based on cd-tetraphenyl porphyrine as a carrier was prepared fordetermination of mno4- ion. this electrode revealed good selectivity toward permanganate ion over a widevariety of anions. effects of some experimental parameters such as nature of the plasticizer, the amounts ofcarrier and additive, and concentration of the internal solution on the potential ...

a highly selective electrode for bromide ion based on aza pyrilium derivative as an excellentionophore is described.the sensor exhibits a good linear response with a slope of ( 60±1 ) mv per decadeover the concentration range of ( 1×10-3 – 9×10-6 m ) , and a detection limit of ( 3×10-6 m ) of bromideions .the electrode response is independent of ph in the range of(4.0 –9.5).selectivity coeffici...

tea is the second most commonly consumed beverage world wide. tea ( camellia sinensis ) is a naturally rich source of fluoride. the quantity of fluoride intake is important in optimizing its dental caries-preventive role. intense concentration of fluoride in tea, can lead to excessive fluoride intake which may cause health problems in turn. the measurement of fluoride intake usually requires in...

Fe2+ ion-selective membrane sensor has been fabricated from polyvinyl chloride (PVC) matrixmembrane containing neutral carrier tetra phenyl porphyrin (TPP) ionophore. The addition ofsodium tetraphenylborate (NaTPB) and the plasticizer DBP has been found to substantiallyimprove the performance of the sensor. The best performance was obtained with the sensor havinga membrane of composition of TPP...

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 cesium ion selective pvc membrane based on parent calix [4] arene was developed for potentiometric determination of cesium in environmental samples. the electrode based on p-5,11,17,23tetra(tertbutyl) 25,26,27,28-tetrahydroxy calix[4]arene(thc) as ionophor ,dibutyl phthalate (dbp)as plasticizer ,sodium tetra phenyl borate(natpb)and oleic acid as lipophilic salt and additive showed the bes...