Determination of Ibuprofen and Phenylephrine in Tablets by High-Performance Thin Layer Chromatography and in Plasma by High-Performance Liquid Chromatography with Diode Array Detection

Continuous wavelet transform for solving the problem of minor components in quantitation of pharmaceuticals: a case study on the mixture of ibuprofen and phenylephrine with its degradation products

The presence of minor components represents a challenging problem in spectrophotometric analysis of pharmaceuticals. If one component has a low absorptivity or present in a low concentration compared to the other components, this will hinder its quantitation by spectrophotometric methods. Continuous Wavelet Transform (CWT) as a signal processing technique was utilized to figure out a solution to such a problem. A comparative study was established between traditional derivative spectrophotometry (Numerical Differentiation, ND) and CWT to indicate the advantages and limitations of each technique and possibility of solving the problem of minor components. A mixture of ibuprofen (IBU) and phenylephrine (PHE) with its degradation products forming a ternary mixture was used for comparing the two techniques. The two techniques were applied on raw spectral data and on ratio spectra data resulting in four methods, namely ND, CWT, Derivative Ratio-Zero Crossing (DRZC) and Continuous Wavelet Transform Ratio-Zero Crossing (CWTR-ZC) methods. By comparing the results in laboratory prepared mixtures, CWT technique showed advantages in analysis of mixtures with minor components than ND. The proposed methods were validated according to the ICH guideline Q2(R1), where their linearity was established with correlation coefficient ranging from 0.9995 to 0.9999. The linearity was in the range 3-40 μg/mL for PHE in all methods, while for IBU it was 20-180 and 30-180 μg/mL in CWT and ND methods, respectively. The CWT methods were applied for quantitative determination of the drugs in their dosage form showing the ability of the methods to quantitate minor components in pharmaceutical formulations.

Development of an eco-friendly HPLC method for the stability indicating assay of binary mixture of ibuprofen and phenylephrine

The development and validation of the stability indicating HPLC technique has contributed to the understanding of the stability profile of ibuprofen (IBU) and phenylephrine (PHE). Stability profile was achieved for PHE; the drug was found to be liable to be influenced by stress oxidative conditions; two oxidative degradants (Deg1 & Deg2) were formed and their structures were confirmed using IR and mass spectrometry. The drugs and degradation products were successfully separated using a gradient elution method on YMC-C8 column with 0.1% hexanesulfonic acid and acetonitrile as a mobile phase at pH 6.6. The flow rate was 1.0 mL/min, and a diode array detector operating at 220 nm was used for UV detection. The retention times of degradants Deg1, Deg2, ibuprofen (IBU), and phenylephrine hydrochloride (PHE) were 2.0, 2.2, 3.2 and 7.0 min, respectively. The proposed method was validated with respect to linearity, accuracy, precision, specificity, and robustness using ICH guidelines. The linearities of ibuprofen and phenylephrine hydrochloride were in the range of 10-100 μg/mL and 0.3-10 μg/mL, respectively. The % recoveries of the two drugs were found to be 100.75 ± 1.44%, 99.67% ± 1.67, and the LOD was found to be 2.75/mL and 0.09/mL for IBU, and PHE, respectively. The method was successfully applied to the estimation of ibuprofen and phenylephrine hydrochloride combination in pharmaceutical dosage form. The proposed technique was validated using ICH guidelines and its greenness was assessed according to Analytical Eco Scale metric (AES). Molecular docking was used to assess the two drugs and PHE oxidative degradants interaction with the stationary phase and to confirm the outcomes of the proposed method with regard to the order of elution of the two drugs and PHE degradation products. Eco-friendly and environmental safety were assessed through the application of one of the most applicable greenness assessment tool; Analytical Eco Scale metric (AES).

Development of HPLC Method for Simultaneous Determination of Ibuprofen and Chlorpheniramine Maleate

One of the most prevalent over-the-counter cold and cough medications is the chlorpheniramine maleate (CPM)–ibuprofen (IBF) combination. A reversed-phase high-performance liquid chromatography (RP-HPLC) method was effectively optimized and developed for the simultaneous detection of chlorpheniramine maleate and ibuprofen in a pharmaceutical formulation. The mobile phase for the RP-HPLC method was an isocratic combination of acetonitrile and 0.01 M acetate buffer at pH 3.8 (55:45; v/v) on an Eclipse Plus C18 reversed phase column. An ultraviolet (UV) detector with a wavelength of 225 nm was used to detect the analytes at a flow rate of 1.0 mL/min. CPM and IBF were satisfactorily eluted, with mean retention times of 2.09 and 6.27 min, respectively. The approach was shown to be linear (R2 > 0.9998 for CPM and 0.9992 for IBF), precise (% RSD 3.02% for CPM and 3.48% for IBF), accurate (% recoveries 97.7–98.9% for CPM and 101–104.5% for IBF), specific, easy to use, sensitive, quick, and robust. Limits of detection (LODs) were found to be 10 and 27 μg/mL for CPM and IBF, respectively. Without interference from excipients, the validated method could be utilized in regular quality control analysis of various dosage combinations of hard gelatin capsules containing CPM and IBF.

Two different synchronous spectrofluorimetric approaches for simultaneous determination of febuxostat and ibuprofen

Two green, simple and sensitive synchronous spectrofluorimetric methods were developed for the first time for the simultaneous estimation of febuxostat (FEB) and ibuprofen (IBU). Method I is constant-wavelength synchronous spectrofluorimetry where FEB and IBU were recorded at 329 and 258 nm, respectively, using Δλ of 40 nm. Method II is constant-energy synchronous spectrofluorimetry using a wavenumber interval of -4000 cm-1. All measurements were carried out in a borate buffer of pH 7 and distilled water for dilution which increased the methods' greenness. The two methods were rectilinear over concentration ranges of 30.0-700.0 ng ml-1 and 0.5-9.0 µg ml-1 in the first method and 20.0-500.0 ng ml-1 and 0.1-8.0 µg ml-1 in the second method for FEB and IBU, respectively. High sensitivity was attained for the two drugs with limits of quantitations (LODs) down to 0.41 and 5.51 ng ml-1 in the first method and 0.25 and 3.32 ng ml-1 in the second method for FEB and IBU, respectively. Recovery percentages were in the range of 97.3-101.9% after extraction from spiked human plasma samples, demonstrating high bioanalytical applicability. The two methods were further applied to tablet dosage forms with good recovery results. The methods' greenness was assessed according to the analytical Eco-Scale and Green Analytical Procedure Index guidelines.