Preparation of PMEO2MA120-OEGMA80- and pHLIP-conjugated GNCs

GNCs were sequentially decorated with temperature-sensitive PMEO₂MA₁₂₀-OEGMA₈₀- and the N-terminus of the pHLIP. Briefly, 10 mL of PMEO₂MA₁₂₀-OEGMA₈₀ (50 mg/mL) was added dropwise to 1 mL of GNCs solution (10 mg/mL) under vigorous stirring. After reacting at room temperature for 3 days, the obtained PMEO₂MA₁₂₀-OEGMA₈₀-conjugated GNCs (denoted as PGNCs) were collected by centrifugation at 10,000 rpm for 10 min and washed with deionized water. Then, the PGNCs were re-dispersed in 1 mL of deionized water. 5 mL of pHLIP (2 mg/mL) was added dropwise to the dispersion and the reaction was maintained for another 24 h. PMEO₂MA₁₂₀-OEGMA₈₀- and pHLIP-conjugated GNCs (denoted as pPGNCs) were collected by centrifugation at 10,000 rpm for 10 min, washed with deionized water and stored at 4 °C for further use.