Development of Cell Chip Based on Track Detector for Examination of Biological Damage by Alpha Particles

A cell chip was developed for the examination of biological damage of cells irradiated by high-energy alpha particles. A CR-39 track detector was employed as a chip substrate to identify high-energy charged particles traversing target cells. Moreover, the patterning of a photopolymer layer spatially controlled the cellular adhesiveness on the chip substrate. HeLa cancer cells were cultured on a micropatterned photopolymer layer. In this way, all the cells on the chip were individually addressed through the block number in the photopolymer pattern. The biocompatibility of the cell chip was examined through a viability test with fluophor reagent and measurement of the cell proliferation rate. HeLa cancer cells on the chip were irradiated with alpha particles and stained with a fluorescent probe molecule for DNA damage detection. The CR-39 substrate was etched by means of an alkali solution during cell incubation. The HeLa cells and alpha tracks were successfully observed by microscopy at once. It was confirmed that fluorescent spots corresponding to DNA damage were located in the direction of the major axis of oval alpha tracks.