Postchromatographic electrochemical detection of carbohydrates at a silver oxide electrode

Abstract

Silver electrodes, when conditioned at sufficiently positive potentials in the presence of a strong base, can be made to form a silver(1) oxide or silver(I1) oxide surface. In the presence of this oxide surface, carbohydrates may be oxidized and quantitated by means of an electrocatalytic scheme. The current which flows to reoxidize the charge-transfer mediator (silver oxide) is directly related to concentration of carbohydrate. Rectilinear response is obtained over at least IXO decades of concentration M to discussed. The application of a high-performance liquid chromatography (HPLC) detector for the separation of some common sugars is illustrated.M). Design of a prototype electrochemical cell and studies of optimum cell conditions are

RETRACTED: Non-enzymatic electrochemical glucose sensor based on silver/silver oxide nano-rods reinforced with multiwall carbon nanotubes

“…Besides these features, Ag/Ag 2 O-f-MWCNTs show a prominent shoulder marked as C / 1 which is found to be complimentary with A / 1 and attributed to the reduction of AgOH back to silver. In case of Ag disk electrode, the intensity of peak A 1 is similar as in the absence of glucose since there is no native silver oxide present on the surface of electrode compared to Ag/Ag 2 O-f-MWCNTs electrode while that of A 2 peak shows a negligible decrease [30] since the outer surface layer of AgO available on the electrode for glucose oxidation is less and the inner layer transformation of Ag 2 O to AgO is perhaps not much affected in the presence of glucose due to geometrical hindrance of the surface layer. Further, Ag 2 O formed through glucose oxidation (A 2 ) would get re-oxidized to AgO at A 3 so the current at peak attributed to outer surface of oxide layer show increase in A 3 (refer Fig.…”

“…Interaction of MWCNTs with silver demonstrate synergistic role in electrochemical redox behavior of silver in alkali solution which is found to be advantageous in glucose oxidation. Choice of silver is due to formation of both, Ag 2 O and AgO at sufficiently positive potentials [30,31]. AgO so formed at þ 0.75 V being unstable facilitates oxidation of glucose.…”

Electrocatalysts for Glucose Electrooxidation Reaction: A Review

“…Platinum [14], silver [16], gold [17], copper [18], nickel [19], iron and cobalt [20] have been commonly used (tested) as electro-catalytic materials for GOR. The experimental results showed that glucose electrooxidation strongly depends on the electrode materials.…”

Optimization of Response of the Silver Oxide Electrode for the Detection of Carbohydrates and Related Compounds

“…In our earlier work we found that carbonate ion can be incorporated into the oxide layer [15]. This article details studies directed towards the optimization of factors such as oxide layer thickness, ratio of silver(II) to silver(I) and mechanical stability of the oxide layer.…”

“…The chemistry of silver has been extensively studied and discussed in this article. Previous studies have indicated that the substrate reacts chemically with silver(II) oxide on the surface of the electrode, which is then re-oxidized at a potential of þ450 mV (vs. SCE) [15,16]. It is important to note that as one scans in the positive direction, the oxidation of the silver(II) is halted at more positive potentials.…”