Simultaneous determination of the active ingredients in composite pseudoephedrine hydrochloride tablets by capillary electrophoresis

Construction of functionalized carbon nanotube@metal oxide nanocomposite for high-performance electrochemical measurement of antipyretic drug in water samples

Acetaminophen (AP) acts as supportive clinical therapy for fever and dysmenorrhea. An overdose of AP may result in severe adverse diseases, such as liver dysfunction. In addition, AP is a key-listed environmental pollutant, which is difficult to degrade in the environment and has serious effects on living bodies. Therefore, the simple and quantitative determination of AP is highly relevant today. In this work, tin dioxide (SnO2) nanoparticles with functionalized multi-walled carbon nanotube (f-MWCNT) as a hybrid composite were prepared by hydrothermal-assisted synthesis. The composite material was characterized by various spectral, morphological, and electrochemical tests. Electrochemical investigations were conducted using a SnO2@f-MWCNT-reinforced electrode for the detection of AP. The composite electrode exhibited better functional properties, which facilitated electron transfer and enhanced electrical conductivity. The calculated low detection limit (LOD) of 0.36 nM is with a wide linear range of concentration from 0.001 to 673 µM. Additionally, the SnO2@f-MWCNT-modified electrode exhibited good anti-interference capability, repeatability, reproducibility, storage, and operational stability. The developed SnO2@f-MWCNT-modified electrode was applied to practical analysis in diverse water matrices (river, drinking, and pond) with acceptable recovery percentages. A synthesized nanoscale metal oxide electrocatalyst is of great interest and an active research area that serves as a foundation for the development of new, cost-effective electrochemical antibiotic drug sensors.

Application of Chemometrics-assisted HPLC-DAD Strategies for Simultaneous Determination of Paracetamol, Pseudoephedrine HCl, Dextromethorphan HBr, Doxylamine Succinate and Saccharin in Syrup Formulation

Introduction:

This study introduces an effective strategy, which combines high performance liquid chromatography coupled with diode array detection (HPLC-DAD) with multivariate calibration methods for the simultaneous determination of paracetamol (PAR), pseudoephedrine HCl (PSE), dextromethorphan HBr (DEX) and doxylamine succinate (DOX) along with sweetener saccharin (SAC) in syrup formulation.

Methods:

PLS-2 and PCR calibration algorithms were selected for data processing. Based on the strategy, all target analytes were rapidly quantified within 5.3 min under the simple isocratic elution (water: methanol, 20/80, v/v) without a complete separation. The performances of the proposed methods were confirmed by analyzing a series of synthetic solutions including different concentrations of analytes.

Results:

The average recovery values were in the range of 100.33 to 103.70%, and the REP (relative error of prediction) values ranged from 1.96 to 4.36% showed that these methods could provide satisfactory predictions.

Conclusion:

Novel HPLC methods coupled with PLS and PCR algorithm enable a simple, fast and low-cost analysis of similar pharmaceutical products for simultaneous determination of the target compounds.

A novel spectrofluorimetric method for the assay of pseudoephedrine hydrochloride in pharmaceutical formulations via derivatization with 4-chloro-7-nitrobenzofurazan

A new highly sensitive and specific spectrofluorimetric method has been developed to determine a sympathomimetic drug pseudoephedrine hydrochloride. The present method was based on derivatization with 4-chloro-7-nitrobenzofurazan in phosphate buffer at pH 7.8 to produce a highly fluorescent product which was measured at 532 nm (excitation at 475 nm). Under the optimized conditions a linear relationship and good correlation was found between the fluorescence intensity and pseudoephedrine hydrochloride concentration in the range of 0.5-5 µg mL(-1). The proposed method was successfully applied to the assay of pseudoephedrine hydrochloride in commercial pharmaceutical formulations with good accuracy and precision and without interferences from common additives. Statistical comparison of the results with a well-established method showed excellent agreement and proved that there was no significant difference in the accuracy and precision. The stoichiometry of the reaction was determined and the reaction pathway was postulated.

Separation and determination of four active components in medicinal preparations by flow injection-capillary electrophoresis

A simple, rapid and accurate method for the separation and determination of paracetamol (Par), pseudoephedrine hydrochloride (Pse), dextromethorphan hydrobromide (Dex) and chlorphenamine hydrogen maleate (Chl) was developed by combination of flow injection and capillary zone electrophoresis for the first time. The analysis was carried out using an unmodified fused-silica capillary (75 mm x 75 microm i.d. x 375 microm o.d., effective separation length of 45 mm) and direct ultraviolet detection at 214 nm, 1.0 kV applied voltage. The optimized running buffer composed of 75 mM sodium borate-15% (v/v) acetonitrile (ACN) (pH* 9.30) was applied for the separation of the four analytes. The separation was achieved in 4.5 min. The sample throughput rate could reach up to 19 h(-1). The repeatability (defined as relative standard deviation) was 0.6%, 1.0%, 2.1%, 1.9% with peak height evaluation and 0.7%, 1.8%, 0.7%, 1.1% with peak area evaluation for Par, Pse, Dex and Chl, respectively. The limits of detection (S/N=3) were 0.22 microg/ml, 0.29 microg/ml, 0.42 microg/ml and 0.70 microg/ml for Par, Pse, Dex and Chl, respectively. The method was successfully applied to determine the four compounds in three cold medicines with recoveries in the range of 97.18-105.15%.

Determination of paracetamol: historical evolution

Paracetamol is a common analgesic and antipyretic drug that is used for the relief of fever, headaches and other minor aches and pains. Their determination in pharmaceuticals is of paramount importance, since an overdose of paracetamol can cause fulminating hepatic necrosis and other toxic effects. Many analytical methodologies have been proposed for the determination of paracetamol. The aim of the present study is to evaluate the utility of different techniques for quantification of paracetamol content in pharmaceutical formulations and biological samples.

Chemometric Determination of Naproxen Sodium and Pseudoephedrine Hydrochloride in Tablets by HPLC

A new chemometric determination by high-performance liquid chromatography (HPLC) with photodiode array (PDA) detection was implemented for the simultaneous determination of naproxen sodium and pseudoephedrine hydrochloride in tablets. Three chemometric calibration techniques, classical least squares (CLS), principle component regression (PCR) and partial least squares (PLS) were applied to the peak area at multiwavelength PDA detector responses. The combinations of HPLC with chemometric calibration techniques were called HPLC-CLS, HPLC-PCR and HPLC-PLS. For comparison purposes the HPLC method called the classic HPLC method was used to confirm the results obtained from combined HPLC-chemometric calibration techniques. A good chromatographic separation between two drugs with losartan potassium as an internal standard was achieved using a Waters Symmetry C18 Column 5 microm 4.6+/-250 mm and a mobile phase containing 0.2 M acetate buffer and acetonitrile (v/v, 40:60). The multiwavelength PDA detection was measured at five different wavelengths. The chromatograms were recorded as a training set in the mobile phase. Three HPLC-chemometric calibrations and the classic-HPLC method were used to test the synthetic mixtures of naproxen sodium and pseudoephedrine hydrochloride in the presence of the internal standard. The HPLC-chemometric approaches were applied to real samples containing drugs of interest. The experimental results obtained from HPLC-chemometric calibrations were compared with those obtained by a classic HPLC method.

Determination of the hydrolysis rate constants and activation energy of aesculin with capillary electrophoresis end-column amperometric detection

Aesculetin is the product of the hydrolysis reaction of aesculin. A high sensitivity and good repeatability method based on capillary electrophoresis with amperometric detection (CE-AD) was developed for simultaneous determination of aesculin and aesculetin in the hydrolysate of aesculin. Under the optimum condition: 10mmol/L KH(2)PO(4)-5mmol/L Na(2)B(4)O(7) (pH 6.0) buffer, separation at 18kV and +900mV (versus Ag/AgCl) as the detection potential, the hydrolysis rate constants of aesculin hydrolysis at 25, 30, 35, 40 and 45 degrees C in 0.1mol/L KOH were obtained as 1.45x10(-2)min(-1), 2.01x10(-2)min(-1), 2.93x10(-2)min(-1), 3.76x10(-2)min(-1) and 5.05x10(-2)min(-1), respectively. It was calculated that the activation energy for aesculin hydrolysis was 49.4kJ/mol.

Simultaneous determination of allantoin, choline and L-arginine in Rhizoma Dioscoreae by capillary electrophoresis

A rapid, easy and reproducible capillary electrophoresis (CE) method for the simultaneous determination of allantoin, choline and arginine in Rhizoma Dioscoreae was developed first time. Under the optimum condition, the three analytes could be well separated within 5 min in a 70 cm (60 cm effective length) x 75 microm i.d. capillary. The relative standard deviations for both migration time and peak height were less than 3.20%. The linear response range was 5.0-150, 0.9-100 and 1.0-200 microg/ml for arginine, choline and allantoin, respectively. The detection limit of three components was 2.0, 0.4 and 0.5 microg/ml for arginine, choline and allantoin, respectively. Contents of arginine, choline and allantoin in the crude drug of Rhizoma Dioscoreae could be easily determined by the proposed method with satisfactory results.

Simultaneous determination of paracetamol and chlorpheniramine maleate by micellar electrokinetic chromatography

A micellar electrokinetic chromatography (MEKC) method was established for determination of paracetamol (PARA) and chlorpheniramine maleate (CPM) in cold tablets. Separation of both drugs, as well as other seven cold remedy ingredients, was achieved in 25.5 min using a sodium dihydrogenphosphate-sodium tetraborate buffer (10 mM, pH 9.0) containing sodium dodecyl sulfate (SDS) (50 mM) and acetonitrile (26% v/v). The effective capillary length of 50 cm, the separating voltage of 15 kV and the temperature of 30 degrees C was optimized. Detection was by a diode array detector at 214 nm. Method linearity was excellent (r(2)>0.999) over the concentration tested (10-250 microg/ml) with good precision and accuracy. Recoveries were good (>99%) with limits of detection of 0.4 and 0.5 microg/ml and limits of quantitation of 2 (%R.S.D.=3.1%) and 4 (%R.S.D.=2.4%) microg/ml, for PARA and CPM, respectively. The developed method was applied to the determination of ingredients in cold tablets and was found to be simple, rapid and efficient.