“…The separation gradient was as follows: 0–3.5 min, mobile phase B increased from 0 to 24.5%, flow rate 0.40 ml/min; 3.5–5 min, mobile phase B increased from 24.5 to 65%, flow rate 0.4 ml/min; 5–5.5 min, mobile phase B increased from 65 to 100%, flow rate 0.4 ml/min; 5.5–7.4 min, mobile phase B was maintained at 100%, flow rate increased from 0.4 to 0.6 ml/min; 7.4–7.6 min, the mobile phase B decreased from 100 to 51.5%, and the flow rate was 0.6 ml/min; 7.6–7.8 min, mobile phase B decreased from 51.5 to 0%, flow rate decreased from 0.6 to 0.5 ml/min; 7.8–9 min, mobile phase B was maintained at 0%, flow rate decreased from 0.5 to 0.4 ml/min; 9–10 min, the mobile phase B was maintained at 0%, and the flow rate was 0.4 ml/min. The column temperature was 40°C (Hu et al, 2021; Xie et al, 2019).…”