A New Validated Potentiometric Method for Batch and Continuous Quality Control Monitoring of Oseltamivir Phosphate (Taminil) in Drug Formulations and Biological Fluids

Abstract

A new validated potentiometric method is described for batch and continuous quality control monitoring of the drug oseltamivir phosphate (Taminil) (OST). The method involves the development of a potentiometric sensor responsive to the drug based on the use of the ion‐association complex of (OST+) cation with phosphomolybdate anion (PMA−) as an electroactive material in a poly(vinyl chloride) matrix membrane plasticized with o‐nitrophenyloctyl ether (o‐NPOE). Optimization of the performance characteristics of the sensor is described. A membrane incorporating the OST‐PMA‐NPOE complex in a tubular flow through detector is used in a two channel flow injection set up for continuous monitoring of the drug at a frequency of ∼30 samples h−1. The sensor shows fast near‐Nernstian response for OST over the concentration range 5.2×10−5–0.8×10−2 M (21.34 µg mL−1–3.23 mg mL−1) with a detection limit of 9.1×10−6 M (3.73 µg mL−1) over the pH range 4.6–6.1. The sensor displays good selectivity for OST drug over some basic drugs, inorganic cations, excipients and diluents commonly used in the drug formulations. Validation of the assay method is tested by measuring the lower detection limit, range, linearity, bias, trueness, accuracy, precision, and between‐day‐variability, within day reproducibility, selectivity and ruggedness (robustness). The results reveal good potentiometric performance of the proposed sensor for determination of OST in pharmaceutical capsules and in biological fluid matrices as well as for testing the dissolution profile of the drug and drug homogeneity.

Detection and quantification of Covid-19 antiviral drugs in biological fluids and tissues

“…OSP was derivatized through the Hantzsch reaction of its primary amino group with acetylacetone and formaldehyde[ 45 ]. The calculated LOQ and LOD values were respectively 0.08 μg/mL and 0.24 μg/mL: these values were considerably lower than LLOQ (7.4 μg/mL) and LOD (3.73 μg/mL), obtained with the potentiometric method proposed by Hassan et al [ 44 ].…”

“…One of the major challenges when developing a method for the quantification of pharmaceutical compounds in bio-fluids and tissues is the practical issues related to acquiring large volumes of sample for the preparation of calibration standards and quality controls [ 42 ]. Although the calibration standards should be prepared in the same biological matrix as the one that is going to be analysed, by adding an internal standard as well [ 28 ], many methods for antiviral drugs’ quantification have been validated in aqueous solutions [ 20 , [43] , [44] , [45] , [46] , [47] , [48] , [49] ].…”

“…A summary of methods published in the last decade, with their main advantages and drawbacks, is reported in Table 3 . Some methods based on potentiometry [ 44 ], spectrofluorimetry [ 45 ] or matrix-assisted laser desorption/ionization (MALDI) [ [106] , [107] , [108] ] were employed. However, as expected, the most widely used methods were based on hyphenated techniques, typically liquid chromatography but also capillary electrophoresis [ 46 ] (CE), coupled to UV-Vis detection or electrospray ionization (ESI) with mass spectrometry (MS).…”

“…Hassan et al [ 44 ] proposed a potentiometric sensor for monitoring oseltamivir phosphate (OSP). The sensor consisted of an ion association complex between the drug and phosphomolybdic acid (OSP-PMA) dispersed in polyvinyl chloride.…”

A New Validated Potentiometric Method for Sulfite Assay in Beverages Using Cobalt(II) Phthalocyanine as a Sensory Recognition Element

“…The potentiometric output was measured with the data acquisition setup. A laboratory-made flow-through tubular potentiometric cell, equipped with CoPC-PVC membrane, was fabricated as previously described [48] and used in a single-channel flow injection system. The cell was assembled and incorporated in a flow injection analysis system.…”