Quantitative Analysis of Methacycline Hydrochloride by Direct Potentiometry Using the Internal Solid Contact Sensor

Abstract

The development of pharmaceutical, clinic and environmental analyses has led to the need of chemical sensors which are robust and easy to construct and to miniaturize, and which require no maintenance during the life period. Among those sensors, internal solid contact sensors (ISCSs), i.e. so-called all-solid state ion-selective electrodes based on the conducting polymers (e.g. PPy, poly(anline) (PAn) etc.) as ion-to-electron transducers have been given special attention, due to their good potential prospects when utilized in miniaturized separation/analytical or microfluidic systems such as HPLC, FIA, CE and μTAC.

Potentiometric Ion Sensors

“…133,134 Polypyrrole was used as an ion-to-electron transducer also in solid-contact ISEs for determination of oxytetracycline hydrochloride and methacycline hydrochloride, which are antibiotics belonging to the tetracycline family. 135,136 Poly(1-hexyl-3,4-dimethylpyrrole), which is soluble in tetrahydrofuran (THF), was used as a solid contact in carbonate-selective ISEs based on a silicone rubber membrane. 137,138 Solution-processable conducting polymers offer some additional flexibility in the electrode manufacturing process, when compared to electropolymerization.…”

“…The physicochemical properties of polypyrrole can be significantly influenced by the doping ion, which offers possibilities of improving, e.g., adhesion of polypyrrole to the ion-selective membrane. This is well-illustrated by the use of polypyrrole doped with cobalt bis(dicarbollide) ions as the solid contact in pH-, Cu 2+ -, and K + -selective microelectrodes. − Furthermore, a composite of polypyrrole and Nafion was applied as the solid contact in pH electrodes based on glass membranes. , Polypyrrole was used as an ion-to-electron transducer also in solid-contact ISEs for determination of oxytetracycline hydrochloride and methacycline hydrochloride, which are antibiotics belonging to the tetracycline family. , …”

Methacycline: A Review of Analytical Methods

“…In another study, Sun and Aboul-Enein [14] developed a sensor for determination of methacycline hydrochloride, based on the use of conducting poly(pyrrole) as solid contact material and methacycline-phosphotungstate as ion exchanger and dibutyl phthalate as the plasticizer. Under the condition of pH 2.7, the linear concentration range, slope (25 ºC) and detection limit of the sensor are 6.4 x 10 -6 -3.0 x 10 -3 M, 52.4±0.2 mV/decade and 4.4 x 10 -6 M, respectively.…”

Weighting Factor in Calculation of Comprehensive Quality Index and Optimization of PVC Membrane Composition for Ion Selective Electrode

“…Most currently we reported a novel evaluation methodology termed as comprehensive quality index (CQI [8] or I CQ [6] ) in a numerical expression for evaluating quality of an ISE or sensor and optimizing the composition of the PVC sensing membrane [6] and internal solid contact sensor. [8,9] The comprehensive quality index (CQI) consisted of the response slope (S), linear range (LR) of the concentration, limit of detection (LD), and response time (T) for an ion-selective electrode or sensor, The index is calculated according to the following equation: CQI ¼ P f i P i , where P refers a parameter of the performance of ISE, f refers a weighed factor of the performance. Obviously, for a given ISE, the magnitude of the value of each weighting factor can influence the value of CQI and optimization of the membrane composition, giving rise to different results for selecting PVC membrane composition.…”