2.3. Fabrication and Purification of Selu-Exo
Selumetinib (ChemScene, Monmouth Junction, NJ, USA, Cat. no. CS-0059, Lot. 78580)-loaded U87 MG-derived exosomes (U87-Selu exo) were fabricated by the electroporation method (4D Nucleofector; Lonza, Basel, Switzerland) using an Amaxa SE Cell Line 4D-NucleofectorTM X Kit L (24RCT, Catalog No. V4XC-1024; Lonza) according to the manufacturer’s instructions. The pulsation program for encapsulation was DS-126. The excess free selumetinib was removed by filtering through an Amicon Ultra 0.5 mL Centrifugal Filter (3K, Catalog No. UFC500396; Millipore) and washed twice with phosphate buffered saline (PBS) at pH 7.4 (1X, Catalog No. 10010 023, Gibco). For selumetinib loading into A549-derived exosomes (A549-Selu exo), Amaxa SF Cell Line 4D-NucleofectorTM X Kits L (24RCT, Catalog No. V4XC-2024; Lonza) and the CM-130 pulsation program were used.