8 arm peg thiol

8 arm PEG-hydroxyl (M_n = 20 kg mol⁻¹, tripentaerythritol core), 8 arm PEG-amine (M_n = 20 kg mol⁻¹, tripentaerythritol core), and 8 arm PEG-thiol (M_n = 20 kg mol⁻¹, tripentaerythritol core) were purchased from JenKem Technology USA. DBCO (dibenzylcyclooctyne) acid was purchased from Click Chemistry Tools (Scottsdale, AZ). All other chemicals were purchased from Sigma Aldrich (St. Louis, MO) or Thermo Fisher Scientific (Waltham, MA), and used as received unless otherwise noted.

PEG (molecular weight (MW) 2 kDa, 4 kDa), K₂CO₃, dichloromethane, acryloyl chloride, KI, Celite® 521, 4-(dimethylamino)-pyridine, N,N′-diisopropylcarbodiimide, 5-norbornene-2-carboxylic acid, NaH, allyl bromide, 2,2-dimethoxy-1,2-diphenylethan-1-one, dithiothreitol, tetrahydrofuran, and thioacetic acid were purchased from Sigma-Aldrich (St Louis, MO, USA). 4-(2-Hydroxyethoxy)phenyl-(2-hydroxy-2-propyl)ketone (Irgacure 2959) was purchased from BASF (Florham Park, NJ, USA). PEGDA (MW 5 kDa) was purchased from Laysan Bio (Arab, AL, USA). Four-arm PEG (MW 5 kDa), 4-arm PEG-thiol (MW 5 kDa), 8-arm PEG (MW 10 kDa), and 8-arm PEG-thiol (MW 10 kDa) were purchased from JenKem Technology (Allen, TX, USA). PEGDA (MW 2 kDa, 4 kDa), 8-arm PEG-norbornene (MW 10 kDa), 4-arm PEG-norbornene (MW 5 kDa), and PEG-dithiol (MW 1.5 kDa) were synthesized in house. BSA was purchased from Fisher Scientific (Pittsburg, PA, USA). The BioRad Protein Assay was purchased from BioRad (Hercules, CA, USA).