Nanopartica sz 100 instrument

The morphological characteristics of SPIONs, BS-S, BS-SP, and BS-SPP were analyzed using various analytical techniques. The particle size, size distribution, and zeta potential of the synthesized nanoparticles were investigated with a Nanopartica SZ-100 instrument (Horiba Ltd., Kyoto, Japan) based on the dynamic light scattering (DLS) technique [19 (link),20 (link),21 ]. To perform the analysis, 30 µL of a 1 mg/mL suspension of SPIONs, BS-S, BS-SP, and BS-SPP were added to 5 mL of distilled water and ultrasonicated for 20 s. Readings were taken, and three runs were conducted for each sample to obtain an average reading. The size of the nanoparticles was examined using transmission electron microscopy (TEM, Jeol JEM 2100, SAIF, Cochin) [20 (link),21 ]. For this analysis, each sample with a concentration of 500 µg/mL in water was ultrasonicated for 20 s. Subsequently, 50–100 µL of the prepared sample was placed on a copper TEM grid. The excess sample was carefully removed using filter paper, and the remaining sample was air-dried before observation under the TEM.

The quality of aptamers was checked by HPLC and MS assay (Figs S1 and S2). The liposomal aptamers were prepared using the lipid hydration method from lipid mixture with some modifications25 (link). The lipid mixture consisted of 18.42% DPPG, 35.52% DPPC, 45.93% cholesterol and 0.13% aptamer (ST-21 or ST-21M). The lipid mixture was dissolved in a mixture of chloroform and methanol (3:1 volume ratio). The organic solvent was evaporated using compressed nitrogen gas, and a thin lipid film was thus generated. The lipid film was then hydrated by 150 mM of SRB solution at 60 °C for 45 minutes. After being fully hydrated, the liposomal aptamers were extruded 30 times through a 200 nm polycarbonate filter membrane and then purified by gel filtration chromatography using Sepharose CL-4B. The sizes of liposomal aptamers were determined by dynamic light scattering (DLS) using nano partica SZ-100 instrument (Horiba, Japan). Whereas, the concentration of liposomal aptamers was determined by flow cytometry with Muse cell analyzer (Merck Millipore, Germany) using 1ml liposomal aptamer solution (10 μl stock liposomal aptamers with 990 μl TBS-sucrose, 100 folds dilution).