Process-Induced Cell Injury in Laser Direct Writing of Human Colon Cancer Cells

Matrix-assisted pulsed-laser evaporation direct-write has emerged as a promising technique for biological construct fabrication. The posttransfer cell viability in matrix-assisted pulsed-laser evaporation direct-write depends on various operating conditions such as the applied laser fluence. To date, the effects of operating conditions such as laser fluence, direct-writing height, and cell density on the posttransfer cell viability have not been well elucidated. This study investigates the effects of operating conditions on the posttransfer cell viability in laser direct writing of human colon cancer HT-29 cells. It has been observed that (1) the HT-29 cell viability decreases from 95% to 78% as the laser fluence increases from 258 to 1482 mJ/cm(2), and the posttransfer cell proliferation capacity does not vary significantly as the laser fluence changes; (2) the direct-writing height does not have noticeable effect on the posttransfer cell viability under low laser fluences (258 and 869 mJ/cm(2)). However, a larger height (such as 29.3 mm) led to an almost 8% viability improvement compared with that of 16.6 mm under a high laser fluence (1482 mJ/cm(2)); and (3) the posttransfer cell viability is not dependent on the cell density for a range from 1 × 10(6) to 1 × 10(7) cells/mL.