Nano z90 nanosizer

The morphological features and mesoporous network structure of the as-synthesized NPs were examined using FESEM (field emission scanning electron microscope) images (FEI Talos F200S). The elemental compositions of the samples were determined using elemental mapping and EDS (energy-dispersive spectroscopy) analyses. The BET (Brunauer–Emmett–Teller) surface area, total pore volume, and pore diameter were obtained using nitrogen sorption isotherms (Micromeritics ASAP-2460, Norcross, GA, United States). The FT-IR spectra were examined using a FT-IR spectrometer (FT-IR 6800 JASCO, Marseille, France) in the 400–4000 cm⁻¹ region using the KBr pellet technique. The zeta potential and size were recorded with a Nano-z90 Nanosizer (Malvern Instruments Ltd., Worcestershire, UK) at ambient temperature.

The fresh complete medium with EV-free FBS (Thermo, America) was used to incubate A549 cells for 48 h. Thereafter, the cells underwent centrifugation at 1500 g and 4 °C for 15 min. After filtration by a 0.22 mm filter (Millipore, America), the supernatant underwent two sequential centrifugations at a high speed of 110,000 g and a temperature of 4 °C for 1 h. A549-Exos were then resuspended in an appropriate volume of phosphate-buffered saline (PBS) and kept at –80 °C for subsequent application. The morphological feature of A549-Exos was observed using transmission electron microscopy. A Nano-z90 Nanosizer (Malvern, UK) was allied to evaluate the size distribution of A549-Exos. Western blot method was allied to analyze the expressional levels of exosomal surface markers such as CD9 and TSG101.