LAUSR

The therapeutic potential of glycyrrhizic acid (GA) with various pharmacological properties is extremely limited owing to its poor water solubility. To solve this problem, nanocarrier-nontoxic Glycyrrhizae Radix et Rhizoma-derived carbon dots (GRR-CDs) with a narrow particle distribution of (1.90 ±0.44) nm were developed by an ecofriendly, simple and low-cost calcination method using GRR as the sole precursor. Then, the solubility of GA was shown to be prominently improved up to 27 times by GRR-CDs via a convenient and cost-effective ultrasonic dispersion method without needing to add any organic reagent. Various technologies were further used to demonstrate the interaction between GA and GRR-CDs. In addition, a release study in vitro exhibited a sustained release of GA for 24 h with a higher release ratio of up to 92.87% compared with that of pure GA. A significantly higher antinociceptive activity of the GRR-CDs-GA complexes compared to unprocessed GRR-CDs and GA was further demonstrated in both hot-plate model and acetic acid-induced writhing model. These results support the promising application of GRR-CDs as a potential tool for improving the solubility and antinociceptive activity of poorly water-soluble drugs, such as GA.