Application of HPLC with ELSD Detection for the Assessment of Azelaic Acid Impurities in Liposomal Formulation

Table 3

LODs and RRFs for the identified impurities.

Impurity	Limit of detection		RF	S  (RFI/RFAA)
	[mg/mL]	[%]
I1	0.090	0.003	4203	0.18
I2	0.009	0.005	11074	0.49
I3	0.004	0.003	19708	0.87
I4	0.005	0.005	33817	1.49
I5	0.005	0.010	27914	1.23
I6	0.004	0.012	31513	1.39
I7	0.004	0.008	40574	1.79
I8	0.002	0.004	38946	1.72
I9	0.003	0.007	46134	2.03
AA			22699	—

RF: recovery factor, RRF: ratio of the recovery factor of an impurity (RF_I) to the recovery factor of azelaic acid (RF_AA), I1–I9: identified impurities, and AA: azelaic acid.