A direct ¹ H NMR spectroscopic method for the quantification of diosmin in <i>Hyssopus officinalis</i> L

The analysis of plant metabolites often relies on time-consuming chromatographic methods. We developed a rapid and green quantitative 1H NMR (qHNMR) methodology for the direct quantification of Diosmin in aerial parts of Hyssopus officinalis L. The protocol involves efficient extraction of Diosmin directly into DMSO-d6, which simultaneously acts as the extraction solvent and the internal standard for quantification, using its residual proton signal. This innovative approach eliminates the need for an external reference standard. The qHNMR method was validated according to ICH guidelines, demonstrating high specificity, linearity (R2 > 0.9994), accuracy (92.7%, 98.0%, 99.6%), and precision (RSD: 4.25% and 4.66%). The method’s applicability was confirmed by the successful analysis of commercial H. officinalis samples. This study establishes a robust, standard-free qHNMR technique for the simultaneous identification and quantification of Diosmin. It represents a significant advancement for the rapid quality control of hyssop and offers a valuable tool for plant metabolomics.