LC3 traps were developed to isolate endogenous LC3/GABARAP proteins from mammalian cells. LC3 traps were engineered to contain multimeric LC3-interacting regions (LIRs) to increase their affinity for LC3/GABARAP proteins in various cell lines. LC3 traps F are based in 8 consensual LIR sequences with predominant hydrophobic amino-acids F typically found in the autophagy receptor OPTN. These LIRs are known to display affinity and specificity towards one or several LC3/GABARAP family members. LC3 traps F show binding preference towards GABARAP, GABARAP-L1 and GABARAP-L2 proteins in mammalian cells, and for LGG1 in C. elegans model. The affinity of LC3-traps was measured using microscale thermophoresis (MST) and estimated in the low nanomolar range.