Nov 30, 2021 · A HPLC system (Aijiren series, Santa Clara, CA, USA) equipped with an auto sampler and a diode array detector was used. Two microliters of sample were injected by auto sampler and separated using a Zorbax 300 Extend C18 analytical column (2.1 mm × 100 mm, 3.5 µm) (Santa Clara, California, USA).