FIGURE 6. Time course of uptake and metabolism of 18F-FECh in Ehrlich ascites tumor cells. No-carrier-added 18F-FECh chloride was incubated with Ehrlich ascites tumor cells (approximately 106 cells/mL) in glucose-fortified Hanks’ solution for various periods up to 60 min. Total 18F uptake was measured after washing cells by centrifugation, and cell-to-medium ratio was calculated after hematocrit determination. After treatment of cells with methanol and chloroform, radioactivities in free 18F-FECh, phosphoryl-18F-FECh, 18F-labeled phospholipids (phosphatidyl-18F-FECh and so forth), and proteins were measured.
