Multi-channel automated programmable liquid exchange system enables high-quality sample preparation for super-resolution microscopy.

The emergence of super-resolution microscopy (SRM) leads to increasing demands on sample quality to faithfully visualize cellular ultrastructure at the nanoscale. For SRM techniques relying on fixed samples, immunofluorescence (IF) labeling is the commonly employed approach. However, traditional manual IF preparation is labor intensive, time consuming, and highly operator dependent, limiting standardization and reproducibility. Here, we report a compact, cost-effective device termed Multi-Channel Automated Programmable Liquid Exchange System (MAPLES) for high-quality IF sample preparation. MAPLES integrates dual peristaltic pumps and multi-channel solenoid valves to enable precise, gentle liquid handling without reagent cross-contamination. Equipped with interchangeable adapters, it supports multiple open-format biological samples. The system exhibits high injection accuracy, low reagent residue, and effective waste removal, making it well suited for multi-step IF workflows. MAPLES-prepared IF samples consistently preserve ultrastructural integrity and fidelity across various biological contexts, satisfying the stringent requirements for stochastic optical reconstruction microscopy (STORM) super-resolution imaging. Furthermore, the flexible modular design of MAPLES allows seamless integration with microscopes for automated sequential drug exchange during live-cell experiments and in situ STORM sample processing. Collectively, MAPLES offers a robust, accessible, and versatile platform for high-quality sample preparation, advancing SRM workflows and enabling diverse extended applications.