Synthesis, characterisation and biological activities of a water-soluble C60-porphyrin dyad

A novel water-soluble covalently—linked Cgo-porphyrin dyad was synthesised and characterised. The dyad consists of a pyridinium porphyrin and a fulleropyrrolidine with an aliphatic linker. The biological activities of the dyad were tested with DNA gel electrophoresis and MTT cancer cell assays. The gel electrophoresis results showed that the dyad cleaved DNA in the presence of light and a reductant, NADH. In the MTT cancer cell assays, the dyad inhibited the growth of ovarian cancer cells in vitra. The cell lines used were the ovarian A2780 line, A2780 473R line (ZD473 resistant) and A2780 CisR line (Cisplatin resistant). The activity of the dyad was increased when samples were exposed to light. The concentration it took to inhibit cell growth by 50% (IC50) for the 473R cell line was 0.7 uM in light compare to 4.3 uM in the dark. The activity of dyad was higher on the resistant strains (IC50 = 0.7 uM for 473R compare to IC50 = 3 MM for A2780 in the presence of light). The results also showed higher activity for the dyad (IC50 = 3 MM) when compared to the parent porphyrin species (IC50 = 13 uM) for the three cell lines. These results provide great promise for the dyad as a potential photodynamic anti-cell cancer drug