Fig. 1. Photosensitization of Pd-Bchl-Ser: effect on cell survival. M2R cells (4x10⁴ cell/well) grown in 96-well plates were preincubated with increasing concentrations of Pd-Bchl-Ser, and either illuminated (light) or not illuminated (dark). Cells were then reincubated for 24 hours in the culture incubator and cell survival was determined using the neutral red assay. Points represent means of triplicate determinations ± s.d.