The use of calixarene as ionophores in potentiometric ion-selective electrodes of naftidrofuryl oxalate using microsized membrane sensors for kinetic study of naftidrofuryl (NFT) degradation

Abstract

KEYWORDSNovel miniaturized polyvinyl chloride membrane sensors in all-solid state graphite and platinum wire supports were developed, electrochemically evaluated and used for the assay of naftidrofuryl oxalate. The naftidrofuryl oxalate sensors were based on the formation of an ionassociation complex between the drug cation and tetrakis-(4-chlorophenyl)borateanionic exchanger as electroactive material and sulfocalix-8-arene as ionophore dispersed in a polyvinyl chloride matrix. Linear responses of 10 -2 -10 -6 M and 10 -2 -10 -5 M with cationic slopes of 56.9 mV and 54.1 mV over the pH range 2-5 were obtained by using the naftidrofuryl oxalate-coated graphite (Sensor 1) and platinum wire (Sensor 2) membrane sensors, respectively. The utility of 4-sulfocalix-8-arene as ionophore had a significant influence on increasing the membrane sensitivity and selectivity. The methods were also used to determine the intact drug in the presence of it's degradate in Praxilene ® tablets, plasma and cerebrospinal fluid with good recovery. Sensor 1 was used to study the kinetics of naftidrofuryl oxalate alkaline degradation that was found to follow a pseudo first-order reaction. The activation energy could be estimated from the Arrhenius plot to be 12.572 Kcal/mol. PotentiometryCerebrospinal fluid 4-Sulfocalix-8-arene Naftidrofuryl oxalate Stabilityindicating method Tetrakis-(4-chlorophenyl)borate

Chemically Modified Carbon Sensors Mixed or Single for the Determination of Cardiovascular Drug Nafronyl Oxalate in Bulk, Praxilene and Human Fluids

“…In addition, the method is easy to operate, high sensitivity, simple, fast static response; reasonable selectivity; long term stability and applicability over a wide concentration range with minimal sample pretreatment and inexpensive making it an excellent tool for the routine determination of Nf in quality control laboratories. The sensor developed is superior as compared with the naftidrofuryl selective sensor described in the literature [9][10][11]. Table 9: Comparison between the published and the current methods for determination of Nf-ISS.…”

“…Naftidrofuryl oxalate (3200-06-4) belongs to a group of medicines called vasodilator in the treatment of peripheral and cerebral vascular disorders [1,2]. Many sophisticated methods of analytical were showed to determine (Nf), including chromatographic [3][4][5][6][7], spectrophotometric [8], electrochemical method [9][10][11], phosphorimetric [12][13][14][15]. The spectrophotometric methods of drug analysis usually suffer from poor selectivity.…”

“…These sensors are capable of considerably enhancing the selectivity in the electroanalytical methods with respect to relatively selective interaction of the electron mediator with the target analyte in a coordination fashion. high selectivity over a wide variety of other cations and compared with sensors previously reported [9][10][11]. In addition, the determination of solubility products of the sparingly soluble naftidrofuryl salts based on CMCPs fabricated in the laboratory and was compared with the solubility products determined by potentiometric/conductimetric method.…”

"RP-HPLC Method Development and Validation for Estimation of Naftidrofuryl Oxalate Using Box- Behnken Design"

“…Naftidrofuryl, chemically it is a (RS)-2-(diethylamino) ethyl-3-(1-naphthyl)-2-(tetrahydro furan-2-ylmethyl) propanoate and it is available in the form of oxalic acid. It is also known as nafronyl, INN, NF, NAFTI or as the oxalate salt nafronyl oxalate [1]. The chemical formula of Naftidrofuryl oxalate is (C26H35NO7) with molecular weight is 473.56 as shown in Figure 1 [2].…”