To further demonstrate the robustness of the self-supervised clustering approach, we applied it to a publicly available mouse brain MALDI MSI dataset. The image size of 240 x 220 pixels is larger than the benchmark data. For the mouse brain MSI data, we generated 1101 ion images Shown in Fig. . We observe diverse spatial patterns of metabolites and lipids localized to different regions of the brain tissue. Ion images showing signal enhancement outside of the tissue region most likely correspond to matrix peaks. Using self-supervised clustering approach, we re-trained the CNN model and clustered 1101 ion images into 35 colocalization groups as shown in Fig. . This process took less than one hour with a single GPU card (Methods).