<p>Analyzing organic, metallic, and anionic components in PM2.5 (particulate matter less than 2.5 µm in size) is critical for understanding its formation, evaluating health risks, and tracing pollution sources. Conventional methods require a combination of multiple offline extraction and detection techniques, leading to high sample consumption, long analysis time, and high costs. To address these challenges, we developed an electrochemistry mass spectrometry (EC-MS) technique that sequentially analyzes organic, metallic, and anionic components in PM2.5. Water and methanol were used to extract water-soluble and fat-soluble components, while EDTA-2Na extracted insoluble metals. Electrochemistry was employed to dissociate oxidizable and reducible species. The extracted components were then ionized and detected online: electrospray for polar organics and anions, Ag⁺ complexation for polycyclic aromatic hydrocarbons, and EDTA complexation for metal ions. The ionized components were detected by mass spectrometry in alternating positive and negative ion modes. This method offers a comprehensive analysis of PM2.5 components with minimal sample consumption and simplified pretreatment. It covers three forms of metals (water-soluble, insoluble, and oxidizable/reducible), multiple anions (NO₃⁻, Cl⁻, CH₃COO⁻, HCOO⁻, NO₂⁻, BO₂⁻), water-soluble dicarboxylic acids, and methanol-soluble organics (fatty acids, aromatic acids, and polycyclic aromatic hydrocarbons). This approach provides an efficient and integrated solution for multi-component detection in PM2.5 analysis.</p>