Green Liquid Chromatographic Methods with Ultraviolet and Tandem Mass Spectrometry Detection: An Application to Ternary Mixture of Paracetamol, Pseudoephedrine, and Cetirizine in Capsules

Background: Effective chromatographic methods were developed for the determination of a multicomponent capsule prescribed for treating the common cold. Greening approaches were adopted as opposed to conventional methods. Objectives: Two novel, green chromatographic methods were established to quantitatively analyze the combination. Methods: First, an HPLC/UV method utilizing green solvents (water and ethanol) and acetic acid to adjust pH at 5 was accomplished. The stationary phase was a ZorbaxSB-C18 column (150 × 4.6 mm, 5 μm), and peaks were detected at 215 nm. The second method is a highly sensitive ultra-performance LC (UPLC)-MS/MS method in which the greening approach was established through the reduction of the analysis time (2 min), decreased solvent consumption (flow rate 300 μL/min), and the utilization of a small volume of samples (injection volume 2 μL). The mixture was separated using a UPLC-BEH C18 column (50 × 2.1 mm, 1.7 μm) with an isocratic elution using methanol–0.1% formic acid aqueous solution (60+40, v/v) as mobile phase and utilizing diphenhydramine as an internal standard. Positive-ion electrospray ionization and multiple reaction monitoring were applied for detection. Results: Recovery percentages for paracetamol, pseudoephedrine, and cetirizine were 101.70 ± 0.969, 100.18 ± 1.563, and 99.67 ± 1.429 for the HPLC method and 99.18 ± 1.172, 100.03 ± 0.883, and 99.82 ± 0.912 for the UPLC-MS/MS method, respectively. Conclusions: The proposed methods efficiently analyzed paracetamol, pseudoephedrine, and cetirizine in Allercet Cold® capsules. Validation of the proposed methods was in accordance with the International Conference on Harmonization recommendations, and statistical comparison with the reported method displayed no significant difference regarding accuracy and precision. Highlights: Paracetamol, pseudoephedrine, and cetirizine were successfully quantified using two chromatographic methods. The HPLC method developed is considered green, using water and ethanol as a mobile phase. The UPLC-MS/MS method was rapid and determined the three drugs with accuracy at nanogram levels.