Wire-Coated Silver(I) Ion-Selective Electrode Based on 2-Mercaptobenzothiazole (MBT) Ionophore: Application to the Determination of Silver in Real Samples

Abstract

A new wire-coated silver ion-selective electrode with a wider concentration range (10 -7 M -10 -1 M) was developed using 2-mercaptobenzothiazole (MBT) as a neutral ionophore. An optimum mixture of PVC, ionophore, dioctylphtalate (DOP) as a plasticizer and sodium tetraphenylborate (NaTPB) as an ion-pairing agent was used in preparing the coatings. The effect of various parameters, such as the electrode bed nature, coating composition and solution pH, on the efficiency of the electrode is described. It has been shown that platinum acts as a more suitable bed for electrode preparation, and exhibits a slope of 59.5 ± 1 mV over the whole range of studied concentrations. The selectivity coefficient of the electrode towards various interfering cations as well as its reproducibility, response time and lifetime of the electrode were estimated. The developed electrode was successfully used for the determination of trace amounts of silver in human hair and photographic waste as real samples and in the potentiometric titration of halides as an indicator electrode.

Improving the detection limits of antispasmodic drugs electrodes by using modified membrane sensors with inner solid contact

“…The results indicated that the detection limits and dynamic ranges of these CWEs are influenced by the nature of the conductive bed, and the detection limit decreases with decreasing the resistivity of the beds ( Table 2). This is true as the electrode potential performance is attributed to the electron exchange mechanism at the coating-bed interface and to the ion-exchange process at the coating-solution interface [26,27]. Silver has the lowest resistivity between the studied elements (1.62 cm −1 ), and as shown in Table 2, the CWEs based on this element have the lowest detection limits.…”

Flame Atomic Absorption Spectrometric Determination of Trace Amounts of Silver after Solid‐Phase Extraction with 2‐Mercaptobenzothiazole Immobilized on Microcrystalline Naphthalene

“…MBT has been used as the chelating agent for the preconcentration and spectrometric determination of Ag(I) [15][16][17], Cu(II) [18], Hg(II) [19,20], Au(III), Pt(IV), and Pd(II) [21]. It has also been used in the construction of ion-selective and modified electrodes [22,23].…”

Flow Injection Spectrophotometric Determination of Sub-mg dm−3 Silver(I) in a Strongly Acidic Solution Containing Concentrated Copper(II) Using a Pyridylazo Reagent

“…Liu et al proposed amido-thiourea immobilized glass beads packing for separation and preconcentration of silver(I) in FIA, which was coupled with AAS. 8 There were also potentiometric detections by silver(I) selective electrodes using 2-mercaptobenzothiazole 9 as an ionophore and using calyx [4]arene as a carrier. 10 However, non of these FIA methods were applicable to practical analyses of silver(I) in coexistence with excess amounts of other metal ions such as copper(II).…”