Transforming a traditional ethnic beverage into highly emissive CDs as a sensitive nanosensor for the anti-malignant hyperthermia drug dantrolene sodium in pharmaceuticals and plasma. An economic and sustainable approach

This work provides a cost-effective, environmentally benign, rapidly prepared, highly fluorescent carbon dots (CDs) using renewable antioxidants-rich feedstock (Tamarindus Indica L.) as the precursor. A home-available and less energy-consuming microwave oven synthesizes CDs within 5 min. The created CDs have the highest fluorescence intensity at 402 nm after being excited at 328 nm, conferring a high luminescence quantum yield of 33.5 %. The prepared CDs provide ultra-sensitive and selective determination of dantrolene sodium (DAN), the only synthetic drug that can manage malignant hyperthermia up to now, and of extraordinary antioxidant properties. The determination is over a wide concentration range of (1.25–100.0 µM) with a limit of detection (LOD) and limit of quantification (LOQ) of 0.07 µM and 0.21 µM, respectively. DAN was estimated in two different pharmaceutical dosage forms, yielding percentage recoveries of 99.49 ± 1.50 and 99.74 ± 0.97. The proposed method was also successfully applied for the assay of DAN in spiked human plasma with a % recovery of 99.55 ± 3.13. Various greenness metrics were used to elucidate the greenness of the nanoprobe. The greenness of this work stems from the fabrication of CDs from natural, widespread, cheap, and edible fruit using a less energy and time-consuming, easily operated, and safe reactor. Moreover, avoiding harsh chemicals and solvents and using distilled water as the diluent renders the method greener. The above-mentioned facts about the proposed method prove it to be a validated analytical approach for different pharmaceutical and biological applications.