Standard Guide for Cell Culture Analysis with SIMS

5.1 The presence of cell growth medium complicates a direct analysis of cells with SIMS. Attempts to wash out the nutrient medium results in the exposure of cells to unphysiological reagents that may also alter their chemical composition. This obstacle is overcome by using a sandwich freeze-fracture method (1). This cryogenic method has provided a unique way of sampling individual cells in their native state for SIMS analysis.

5.2 The procedure described here has been successfully used for imaging Na⁺ and K⁺ ion transport (3), calcium alterations in stimulated cells (4,5), and localization of therapeutic drugs and isotopically labeled molecules in single cells (6). The frozen freeze-dried cells prepared according to this method have been checked for SIMS matrix effects (7). Ion image quantification has also been achieved in this sample type (8).

5.3 The procedure described here is amenable to a wide variety of cell cultures and provides a way for studying the response of individual cells for chemical alterations in the state of health and disease and localization of isotopically-labeled molecules and theraputic drugs in cell culture models.