The iMLayer AERO automatic sprayer was designed to simplify the pretreatment of samples and enable users to obtain images with high sensitivity and high spatial resolution easily. The iMLayer AERO device automates the spraying process, contains an automatic rinsing mechanism, and has an in-chamber humidity control function. These features enable sample preparation with reproducibility, independent of the environment or the skill of the operator. The iMLayer AERO sprayer works by incorporating a sample stage that moves at a controlled rate while maintaining the same distance from the spray nozzle, enabling stable matrix spraying. Over multiple strokes, the sample becomes laminated with the matrix crystals, enabling high sensitivity and high spatial resolution. Users can implement a two-step matrix deposition combining vapor and spray deposition methods to acquire high-spatial-resolution images (5 μm to 10 μm) and increase sensitivity.