Strengths:

The ABTS cationic radical is soluble in both organic and aqueous media in contrast to the DPPH radical, which dissolves only in organic medium. The ABTS assay can, thus, be used to screen both lipophilic and hydrophilic samples [16] Can be used to determine the antioxidant capacity of numerous compounds, namely carotenoids, phenolic, and plasma [12] The ABTS assay produces reproducible results [6] The ABTS•+ radical is stable for more than two days when stored in the dark at ambient temperature compared to DPPH, which has a rather short life, however, Gupta [27] stated that the radical solution is stable for a few months when stored in the refrigerator. We can say that the stability of the ABTS•+ radical solution remains debatable [12] Good correlation is usually reported with bioactive compounds (phenols, flavonoids), with generally, a regression factor R > 0.8

Limitations:

The ABTS•+ assay is often criticized because the ABTS•+ radical does not exist naturally (not found in any biological system) and should be chemically generated. Thus, some literature argued that the ABTS•+ radical cannot represent in vivo system [38] Slow reaction for the generation of the ABTS•+ radical, which takes about 12–16 h compared to DPPH, which is readily available commercially Like DPPH, the ABTS•+ radical exhibits high steric hindrance around its nitrogen-centred atom and thus, does not represent a good model for highly reactive radicals, namely OH•, NO•, O2•− or LO(O)•, which are present in numerous biological samples [32]