Green gradient RP HPLC for determination of cytarabine and granisetron in spiked human plasma with greenness and whiteness assessment

Cytarabine is a widely used chemotherapeutic agent for the treatment of leukemia, while granisetron is commonly co-administered to manage chemotherapy-induced nausea and vomiting. In this study, an environmentally friendly, sensitive, and precise gradient RP-HPLC method was developed and validated for the simultaneous determination of cytarabine and granisetron in spiked human plasma samples. Chromatographic separation was achieved on a RP-C18 column (25 cm × 4.6 mm, 5 μm particle size) using gradient elution with a mobile phase consisting of water containing 0.1% (v/v) triethylamine and methanol, adjusted to pH 6 with orthophosphoric acid, and detection was performed at 290 nm. The method showed high sensitivity and linearity over the concentration ranges of 0.1–20 µg/mL for cytarabine and 0.3–20 µg/mL for granisetron in both plasma samples and standard solutions. The method was validated according to FDA and ICH guidelines, confirming satisfactory accuracy, precision, and specificity. Environmental sustainability was assessed using AGREE metric, the Green Analytical Procedure Index (GAPI), and Multicriteria Assessment of Green Analytical Chemistry (AMGAC), demonstrating an acceptable environmental profile with an AGREE score of 0.68. The developed method provides a reliable, cost-effective, and eco-friendly analytical tool suitable for therapeutic drug monitoring of cytarabine and granisetron in clinical settings.