Quantification of Naringin by RP-HPLC

The content of naringin was determined using a previously published validated RP-HPLC method [11 (link)]. All test samples were diluted suitably with mobile phase, and the chromatographic separation was performed using an isocratic elution. The mobile phase consisted of a mixture of potassium phosphate buffer (10 mM, pH adjusted to 3.6 using dilute orthophosphoric acid) and acetonitrile (25:75) and delivered at a flow rate of 1 mL/min. The HPLC system consisted of a pump (Jasco PU-2080 Plus, Intelligent HPLC pump, Jasco, Tokyo, Japan) connected to Detector (Jasco 2075, Intelligent UV–vis detector, Jasco, Tokyo, Japan). The separation was carried out at 20 °C, on a reversed-phase C18 HPLC column (Qualisil^® BDS, 250 mm × 4.6 mm, 5 μm particle size, Qualisil, Agilent Technologies, Mumbai, Maharashtra, India). An injection volume of 20 μL was used. Detections were carried out at 284 nm.