Authors:Jun Zhang, Kaimin Liu, Gengmei Xing, Tongxiang Ren, and Shukuan Wang
Gd@C82(OH)40 has been developed as a new generation of MRI contrast agent. But recently, it was found that Gd@C82(OH)x with a larger number of OH (x>36) would lead to cage break and hence, release of highly toxic Gd ions. We synthesized the more stable Gd@C82(OH)x with less OH-number, Gd@C82(OH)16, and studied its proton relaxivity and MRI images. The results indicate that Gd@C82(OH)16 also gives high proton relaxivity, even higher than that of (NMG)2-Gd-DTPA. The bio-distribution indicated that Gd@C82(OH)16 tends to be entrapped in the liver and kidney and remained in tissue for about 2 hours. The results suggest that the more
stable metallofullerene derivative Gd@C82(OH)16 can be the potential candidate of the new MRI contrast agent.
Authors:Jun Tang, Gengmei Xing, Hui Yuan, Xingfa Gao, Long Jing, Shukuan Wang, Yue Cheng, and Yuliang Zhao
The electronic properties of the metal atoms encaged in a fullerence cage were investigated using synchrotron X-ray photoelectron
spectroscopy. Systematic variations in photoemission of valence band of Gd@C82, Gd@C82(OH)12, and Gd@C82(OH)22 were observed in Gd 5p levels. The results suggest that the electronic properties of the inner metal atom can be efficiently
modulated by surface chemistry of the fullerene cage.
Authors:Yue Cheng, Kaiming Liu, Gengmei Xing, Hui Yuan, Long Jing, and Yuliang Zhao
The water-solubilization of metallofullerenes is important for their potential applications, but their formation processes
are still not clear, and the formation yield is uncontrollable. In this paper, we quantitatively studied the water-solubilizing
process of Gd@C82 with hydroxylation reaction using ICP-MASS techniques. For the first time, it was found that the formation yield of the multihydroxylated
Gd@C82 is declined quickly with the break up of carbon cage of Gd@C82 in the hydroxylated processes. The observation revealed a way to control the hydroxylation processes and increase the formation
Nanosized copper particles are widely used in fields of lubricants, polymers/plastic, metallic coating and ink. Recently,
we found that copper particles in different sizes can lead to different toxicological effects. To clarify the target organs
of copper particles of different sizes, the inductively coupled plasma mass spectroscopy (ICP-MS) was employed to evaluate
the distribution of copper in different organs of mice after a single dose oral exposure. The results suggest that the main
target organs for copper nanoparticles are kidney, liver and blood. Liver is the main damaged organ.
Recently, it was reported that the toxicity of copper particles increases with the decrease of the particle size on a mass
basis. To understand this phenomenon, inductively coupled plasma mass spectrometry (ICP-MS) techniques and in vitro chemical
studies were carried out to explore how they produce toxicity in vivo. The results suggest that when the sizes of particles
become small and down to a nanoscale, copper becomes extremely reactive in a simulative intracorporeal environment. The nanosized
copper particles consume the hydrogen ions in stomach more quickly than micron ones. These processes further convert the copper
nanoparticles into cupric ions whose toxicity is very high in vivo.