Gelatin gels as multi-element calibration standards in LA-ICP-MS bioimaging: fabrication of homogeneous standards and microhomogeneity testingElectronic supplementary information (ESI) available: Experimental section, Table S1 and Fig. S1-S3. See DOI: 10.1039/c7an01361b

Highly homogeneous multi-element gelatin calibration standards were fabricated for quantitative LA-ICP-MS bioimaging. Heterogeneity issues caused by the so-called "coffee-stain" and/or "Marangoni" effects were found to be element-dependent but could be circumvented by careful selection of drying/setting conditions. A micro-homogeneity test was developed for certification of the standards. Fabrication of homogeneous multi-element gelatin standards for quantification purposes in 2D/3D LA-ICP-MS imaging and development of a microhomogeneity test.