# Greenness, blueness, and whiteness evaluation of a quantitative nuclear magnetic resonance procedure for concurrent assay of aspirin and omeprazole in their single and fixed-dose combined tablets

## TL;DR

This paper presents an eco-friendly and precise method using NMR to measure aspirin and omeprazole in single and combined tablets for better treatment monitoring.

## Contribution

A new green NMR method for concurrent and accurate quantification of aspirin and omeprazole in pharmaceutical formulations.

## Key findings

- The NMR method showed excellent linearity (r = 0.9999) and precision (%RSD < 1.08) for both drugs.
- The method is environmentally friendly and does not require labeling or pretreatment steps.
- The technique was successfully applied to both single and fixed-dose combination tablets.

## Abstract

The Food and Drug Administration recently approved a fixed dose combination of aspirin and omeprazole that has been introduced for the treatment of gastrointestinal disorders, as it reduces the risk of upper gastrointestinal and cardiovascular adverse events in aspirin-treated patients. Therefore, an optimized eco-friendly, simple, fast, and precise quantitative nuclear magnetic resonance spectroscopy technique was presented for the concurrent estimation of that mixture in their single and combined dosage forms. The quantitative nuclear magnetic resonance spectroscopy concurrent estimation of both drugs was achieved using phloroglucinol as the internal standard and dimethyl sulfoxide as a deuterated solvent. An ideal set of acquisition parameters was determined to be 128 scans, 10 s relaxation latency, and 90° pulse angle. The selected quantitative signal of aspirin was the doublet of doublet signal appeared at 7.945 ppm, while that of omeprazole was the singlet signal at 8.18 ppm. The singlet signal at 5.69 ppm was selected for the internal standard. The spectra were subjected to integration, baseline correction, and auto phase correction. The developed quantitative proton nuclear magnetic resonance spectroscopy method was found to be rectilinear over the range of 0.05–4.0 mg mL−1 for both drugs. The detecting and quantifying limits for both drugs were approximately 0.01 and 0.03 mg mL−1, respectively. Neither labelling nor pretreatment steps were needed to assay the studied drugs using our developed quantitative nuclear magnetic resonance spectroscopy method. The proposed nuclear magnetic resonance spectroscopy approach was effectively evaluated in terms of linearity (r = 0.9999), accuracy, and precision (%RSD < 1.08). Furthermore, the suggested technique was investigated to analyze the studied drugs in their single and combined dosages. This work enables clinicians to simultaneously monitor aspirin and omeprazole levels in both single and fixed-dose combination tablets, ensuring precise dosing and effective treatment management. For patients, it supports safer therapy by reducing the risks associated with improper dosing or drug interactions in combination therapies. After evaluating the method's greenness, whiteness and blueness, it was determined that the suggested approach was environmentally friendly. The suggested approach was compared with the previously reported methods from both an analytical and eco-friendly perspective.

The online version contains supplementary material available at 10.1186/s13065-025-01477-3.