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

Table 1

Results of the assessment of the precision of the chromatographic system due to the assessments of nine identified impurities of the azelaic acid.

Measurement	Peak area (A) for the assessed identified impurities:  [mV×s]
	I1	I2	I3	I4	I5	I6	I7	I8	I9
1	258.113	1203.014	1706.031	1746.713	2830.966	2752.13	4702.942	3528.136	3821.195
2	267.883	1201.028	1717.689	1736.138	2809.523	2760.488	4735.845	3499.348	3827.302
3	269.431	1207.302	1710.66	1735.395	2805.159	2751.771	4728.282	3506.829	3831.149
4	261.999	1208.041	1717.319	1757.147	2842.288	2740.871	4701.934	3511.741	3804.322
5	265.122	1193.801	1715.516	1746.554	2801.162	2787.357	4698.756	3501.03	3805.952
6	259.204	1204.02	1698.914	1756.218	2805.766	2754.597	4730.213	3490.329	3821.493
7	266.327	1193.193	1696.215	1744.038	2824.143	2751.029	4736.137	3493.413	3844.485
8	258.348	1201.998	1699.815	1743.793	2829.951	2765.384	4703.253	3532.354	3824.421
𝑋	263.303	1201.550	1707.770	1745.750	2818.620	2757.953	4717.170	3507.898	3822.540
SD	4.49	5.53	8.75	7.99	15.14	13.88	16.77	15.41	13.05
RSD	1.7	0.5	0.5	0.5	0.5	0.5	0.4	0.4	0.3

I1–I9: identified impurities, 𝑋: average, SD: standard deviation, SRD: relative standard deviation.