. Author manuscript; available in PMC: 2014 Apr 17.

Published in final edited form as: Bioconjug Chem. 2013 Apr 2;24(4):658–668. doi: 10.1021/bc300632w

Table 2.

Cytotoxicity of drugs and drug conjugates in cancer cells

Drug formulations	IC₅₀ value (μM)^*	Enhancement factor
Etoposide	12.3	-
HA-ETO	6.3	1.9
CHA-ETO	3	4.2
Salinomycin	5.1	-
HA-SAL	3.2	1.6
CHA-SAL	0.9	5.4
Curcumin	19	-
HA-CUR	70	0.3
CHA-CUR	9	2.1

Cytotoxicity was measured after 72-h treatment. Enhancement factor shows the drug conjugate efficacy compared to free drug. CHA cytotoxicity (IC₅₀) was > 5 mg/mL. The data are average of eight parallel measurements. Etoposide and salinomycin conjugates were tested in MDA-MB-231/F cells; curcumin conjugates were tested in MIA PaCa-2 cells.