MOF-MWCNT Functionalized Sponge as a Single-Adsorbent in Sin-QuEChERS Cleanup Platform for Efficient Multi-Pesticide Analysis in Codonopsis Radix

A novel Sin-QuEChERS cleanup method was developed for multi-pesticide residue analysis in Codonopsis radix by introducing a compressible composite adsorbent—isoreticular metal-organic framework-3 (IRMOF-3)/multi-walled carbon nanotubes (MWCNTs)-functionalized melamine sponge (MOF/MT@MeS). This innovative material enables one-step matrix cleanup through immersion and physical squeezing, eliminating the need for centrifugation and multiple sorbents required in conventional QuEChERS method. The covalent integration of amino-functionalized IRMOF-3 and MWCNTs exploits synergistic hydrogen bonding and π–π interactions for efficient purification. The composite significantly suppressed matrix effects (–12.7 to 17.4% vs –30.9 to 32.8%). Compared to traditional adsorbent materials, the composite yielded more consistent pesticide recoveries (90.4–117.9% vs 83.7–123.4%). The validated method exhibited excellent linearity (R², 0.9934–0.9991), high sensitivity (detection limits 0.54–8.33 μg/kg), and satisfactory accuracy with recoveries of 72.4–111.9% and RSD ≤14.1%. This work establishes functionalized sponge-based adsorbents as an efficient, rapid, and reliable alternative for pesticide monitoring in complex botanical matrices.