Precise Electrical Detection of Curcumin Cytotoxicity in Human Liver Cancer Cells

Curcumin is a polyphenol extracted from the roots of Curcuma plants that exerts potential anticancer effects. However, owing to its low toxicity, curcumin is known to be effective only at high doses. Here, we report the highly sensitive assessment of curcumin toxicity in human liver cancer cells, which was facilitated using a fabricated conductive platform and an electrochemical detection method. To identify the best platform for assessing cell viability, both electrochemical deposition time (0–150 s) and RGD peptide concentrations (0–0.1 mg/mL) were varied. Unlike other cell types, liver cancer cells showed the highest electrical signals without the modification of cell adhesion peptides. With 120 s of gold deposition under peptide-free conditions, 10,000 cells/chip were detectable within a linear range of 10,000–500,000 cells. Notably, even at low concentrations (e.g., 20 µM), curcumin could inhibit liver cancer cell-specific electrical signals by 45%, which would be undetectable in conventional colorimetric assay (CCK-8). The half-maximal inhibitory concentration (IC₅₀) of curcumin for HepG2 cells was 23.63 µM, which indicates 3.71-fold higher sensitivity than that determined in the CCK-8 assay (IC₅₀ = 87.88 µM). Hence, the developed conductive cell culture platform, in combination with the electrochemical detection method, could serve as a promising tool for detecting toxicity and/or anticancer activity of food-derived compounds in cancer/normal cells.