Table 5.

Overview of buffer studies. Studies investigating polysorbate oxidation using different buffer systems in the presence (+) and absence (-) of protein. Studies independently investigating one buffer system or using different buffer systems without a direct comparison are not included.

Buffer system	Study	Polysorbate quality	Protein
Sodium-citrate	Gopalrathnam et al. (2018) (Gopalrathnam et al., 2018)	PS80 (quality not defined)	-
	Doyle et al. (2019) (Doyle et al., 2019)	PS80 MC	-
	Brovč et al. (2020) (Brovč et al., 2020a)	PS20 MC and PS80 MC/AO	-
	Bensaid et al., (2022) (Bensaid et al., 2022)	PS80 MC/AOa	+/-
Citrate	Liu et al. (2022) (Liu et al., 2022a) b	PS80 MC/ChP	-
Histidine-hydrochloride	Zhang et al. (2018) (Zhang et al., 2018)	PS20 MC	-
	Gopalrathnam et al. (2018) (Gopalrathnam et al., 2018)	PS80 (quality not defined)	-
	Doyle et al. (2019) (Doyle et al., 2019)	PS80 MC	-
	Brovč et al. (2020) (Brovč et al., 2020a)	PS20 MC and PS80 MC/AO	-
	Liu et al. (2022) (Liu et al., 2022a) b	PS80 MC/ChP	-
	Bensaid et al., (2022) (Bensaid et al., 2022)	PS80 MC/AOa	+/-
	Peters et al., (2022) (Peters et al., 2022)	PS80 MC	-
Sodium-acetate	Zhang et al. (2018) (Zhang et al., 2018)	PS20 HP	-
	Kranz et al. (2019) (Kranz et al., 2019)	PS20 MC/AL PS80 MC/AO	-
	Bensaid et al., (2022) (Bensaid et al., 2022)	PS80 MC/AOa	+/-
Sodium-phosphate	Doyle et al. (2019) (Doyle et al., 2019)	PS80 MC	-
	Brovč et al. (2020) (Brovč et al., 2020a)	PS20 MC and PS80 MC/AO	-
	Peters et al., (2022) (Peters et al., 2022)	PS80 MC	-
Histidine-acetate	Zhang et al. (2018) (Zhang et al., 2018)	PS20 HP	-
Sodium-succinate	Brovč et al. (2020) (Brovč et al., 2020a)	PS20 MC and PS80 MC/AO	-

^aBensaid et al. (2022): not clearly defined which PS80 was used in the buffer comparison.

^bLiu et al. (2022): not clearly defined which counter ion was used