Objective: To establish a method of multi-assay by single-marker (QAMS) for simultaneous determination of pseudolaric acid B-O-β-D-glucoside (PABG)

pseudolaric acid C (PAC) and pseudolaric acid B (PAB) in Fufang Tujingpiding. Method: Using pseudolaric acid B as the internal reference substance

the relative correction factors (RCF) of the other two diterpenoids were 0.681 4 and 1.225 3 respectively. The other two diterpenoids were simultaneously calculated according to their RCFs. The content of these two diterpenoids in 17 samples was also determined by external standard method

comparing two methods to validate the accuracy and feasibility of the new method. Result: Three diterpenoids in 17 batches of Fufang Tujingpiding were determined by the new method

and there were no significant differences between the calculated values and the measured values. Conclusion: The new method is feasible and accurate to evaluate the content of three diterpenoids in Fufang Tujingpiding

which can be used as the quality control of Fufang Tujingpiding.