5.1 Pressing cryosections flat onto a conducting substrate has been one of the most challenging problems in SIMS analysis of cryogenically prepared tissue specimens. Frozen cryosections often curl or peel off, or both, from the substrate during freeze-drying. The curling of cryosections results in an uneven sample surface for SIMS analysis. Furthermore, if freeze-dried cryosections are not attached tightly to the substrate, the impact of the primary ion beam may result in further curling and even dislodging of the cryosection from the substrate. These problems render SIMS analysis difficult, frustrating and time consuming. The use of indium as a substrate for pressing cryosections flat has provided a practical approach for analyzing cryogenically prepared tissue specimens (1).⁴

5.2 The procedure described herein has been successfully used for SIMS imaging of calcium and magnesium transport and localization of anticancer drugs in animal models (2, 3, 4, 5).

5.3 The procedure described here is amenable to soft tissues of both animal and plant origin.