Jem f200

The SPIONs were synthesized using a thermal decomposition method presented in a previous study [49 (link)]. Briefly, 1.08 g iron(III) chloride and 3.65 g sodium oleate were dissolved in a 28 mL mixture of ethyl alcohol, distilled water (DW), and hexane. The mixture was thermally evaporated at 60 ${}^{\circ }$ C for 4 hrs using a 3-neck flask under constant nitrogen influx to form an iron oleate complex. The mixture was washed with DW three times, and excess remaining hexane was evaporated at 40 ${}^{\circ }$ C for 30 min using a rotary evaporator (SB-1300, Singapore). The collected 1.8 g iron oleate, 0.312 g oleic acid, and 3 g N-tetracosane were dissolved in 9 mL 1-octadecene. The mixture was evaporated at 320 ${}^{\circ }$ C for 1 hr in a 3 neck flask with vigorous stirring to induce the nucleation/growth phase of nanocrystals. The resulting solution was cooled at room temperature, followed by the addition of 15 mL hexane. Synthesized SPIONs were separated from hexane using a magnetic field, and the SPION-containing solution was washed three times with acetone. The images and X-ray diffraction (XRD) pattern of SPIONs nanocrystals were obtained using transmission electron microscopy (TEM, JEM-F200, Japan) and XRD machine (D8 Advance, Bruker, USA) to characterize the crystals, respectively.