A simple method for HPLC retention time prediction: linear calibration using two reference substances

Chinese Medicine

Table 4 Comparison result by four methods (Psoraleae)

Method	Maximum of Δt_R/min	Average of Δt_R/min	Number of positive columns^a
Unadjusted RR	3.494	0.804	2
Adjusted RR	3.001	0.886	3
Prediction by two points	2.194	0.599	5
Validation by multiple points	1.689	0.465	9

^aThe columns which meet the following requirements are called positive column, (1) the resolution of peaks meets the requirements; (2) Δt_R of all pending test compounds are no more than t_RL (for Psoraleae is 1.2 min)

ISSN: 1749-8546