Trifluoroacetic acid

P-Terphenyl, 1-methyl-4-piperidone, Trifluoroacetic acid (TFA), 4-Vinylbenzyl chloride (VBC), iodomethane (CH₃I), trifluoromethanesulfonic acid (TFSA) were obtained from Energy Chemical. M-Terphenyl was purchased from Aladdin. Dichloromethane (CH₂Cl₂), potassium hydroxide (KOH), potassium carbonate (K₂CO₃), DMSO, sodium hydroxide (NaOH), sodium chloride (NaCl), and acetone were acquired from Sinopharm. The polymerization inhibitor needs to be removed before VBC application, and no further purification is required for other chemicals.

Piperidine, DBU, trifluoroacetic acid and acetonitrile (ACN) were purchased from Energy Chemical Technology (Shanghai) Co., Ltd. 2,4,6-Trimethyl-1,3,5-triazine (TMT), 2,4,6-trimethylpyridine-3,5-dicarbonitrile (DCTP), 2,4,6-tris(4-formylphenyl)-1,3,5-triazine (TFPT), 1,3,5-tris(4-formylphenyl)benzene (TFPB), 4-[4-[3,5-bis[4-(4-formylphenyl)phenyl]phenyl]phenyl]benzoic acid (DAFB), 4,4,4-(benzene-1,3,5-triyltris(ethyne-2,1-diyl))tribenzaldehyde (BTTA), 4,4’-biphenyldicarboxaldehyde (BDA), 4,4”-p-terphenyldicarboxaldehyde (TDA), 4-[2-(4-formylphenyl)ethynyl]benzaldehyde (EDA), tris(4-formylphenyl)amine (TPA), and p-phenylenediamine (Pa) were purchased from Jilin Chinese Academy of Sciences-Yanshen Technology Co., Ltd. Tetrahydrofuran (THF), 1,4-dioxane, mesitylene, benzaldehyde, NaOH, KOH, EtONa, N,N-dimethylformamide (DMF), 2,2,6,6-tetramethylPiperidine (TEMP), ethanol, methanol, CH₂Cl₂, acetone, and n-BuOH were purchased from Sinopharm Chemical Reagent Co., Ltd. Ultrapure water was prepared from the Millipore system (18.25 MΩ-cm). All the electrochemical measurement used phosphate buffered (PBS, pH = 7.5) containing mixture solutions of 0.1 M KCl, 0.1 M K₂HPO₄, and 0.1 M KH₂PO₄ as the electrolyte.

Paclitaxel (PTX) and allyloxypoly (ethylene glycol) with a molecular weight of ∼2000 (APEG_2k-OH) were purchased from Sigma Aldrich (Shanghai, China). 4-Acetamidophenol, thiodiglycolic anhydride, 4-(dimethylamino)pyridine (DMAP), 2-hydroxyethyl methacrylate (HEMA), 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide hydrochloride (EDC·HCl), cysteamine, 2,2-dimethoxy-2-phenylacetophenone (DMPA), N,N′-dicyclohexylcarbodiimide (DCC), azobisisobutyronitrile (AIBN), trifluoroacetic acid (TFA), and 3-(maleimido)propionic acid N-hydroxysuccinimide ester (MAL-NHS) were purchased from Energy Chemical (Shanghai, China). Anti-PD-L1 peptide CNYSKPTDRQYHF (pep) was purchased from Bankpeptide Biological Technology Co, Ltd (Hefei, China). All other organic reagents were purchased from Sinopharm Chemical Reagent Co, Ltd (Shanghai, China). APC-αPD-L1was purchased from Biolegend (USA). The chain transfer agent, PETTC, was synthesized as previously reported [24 (link)]. BALB/c mice were purchased from the SLAC Laboratory Animal Co, Ltd. (Shanghai, China). The animal experiments were approved by the Animal Care and Use Committee of Zhejiang University and were performed according to the guidelines.