Amounts of Cu and Fe in MCF-Cu and NSM/MCF-Cu particles were confirmed again by using ICP-AES analysis and are presented in Table 2. The amount of Fe in NSM/MCF-Cu was 8.62 × 104 ppm. Therefore, the NSM/MCF-Cu particles could be easily recovered by magnetic separation. The amount of Cu in NSM/MCF-Cu was about 5 times higher than that Ezatiostat in MCF-Cu.
ICP analysis of the MCF-Cu and NSM/MCF-Cu.Sample IDCu (ppm)Fe (ppm)MCF-Cu6.05 × 103–NSM/MCF-Cu3.46 × 1048.62 × 104Full-size tableTable optionsView in workspaceDownload as CSV
If the organosilane ligand of Cu complex with pyridine nitrogen were grafted to the silica surface in the same manner as the MCF-Cu, more significant decrease of surface area in NSM/MCF-Cu was expected due to larger amount of Cu. However, it was noted that the decreased surface area of NSM/MCF-Cu (272 m2/g, 0.33 cm3/g) from that of NSM/MCF was similar to the difference observed between MCF-Cu and MCF, as shown in Table 1. It indicates that a certain amount of organosilane ligand can be grafted on the surface of NSM and MCF because NSMs bound by TSBN were positioned at the pores in the MCF.