Strategies to stabilize dalbavancin in aqueous solutions: Section 4—identification of heat degradation products in 2-hydroxypropyl-β-cyclodextrin and divalent metal ion solutions at pH 4.5 and 7.0

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Table 4 The effect of divalent metal ions on the yields of degradation products of dalbavancin found after stressing at 70 °C for 5 days in 10 mM acetate buffer

Compound ID	Relative EIC peak intensity (%)^a			Fraction of total HPLC-UV peak area (%)^b
Compound ID	AcB10Ca10	AcB10Mg2	AcB10Zn2	AcB10	AcB10Ca10	AcB10Mg2	AcB10Zn2
MAG	105	99	101	51.2	53.6	50.5	49.0
DB-Iso-DP1	73	96	60	0.97	0.71	0.92	0.61
DB-DP1	96	97	74	0.77	0.62	0.76	0.62
DB-Iso-DP2	76	98	68	1.6	1.2	1.6	1.1
DB-DP2	85	99	69	1.1	0.90	1.1	0.76
Dalbavancin (B0)	91	97	106	39.5	38.7	39.9	42.1
Unknown degradants	None detected	None detected	None detected	4.9	4.3	5.1	2.5
Total degradants	N/A	N/A	N/A	60.6	61.3	60.0	58.1

^aLevels of degradation products are expressed relative to their levels in acetate buffer without metal ions
^bLevels of degradation products are expressed as the area under their HPLC peak as a percentage of the total peak area