TF and glioma: In this study, three main findings were generated: first, Tf-conjugated SPIO (Tf-SPIONs) is suitable for MR imaging; secondly Tf-SPIONs could be specifically and efficiently internalized by C6 glioma cells, along with prolonged retention and detection by MR imaging; and thirdly Tf-SPIONs could create the obvious contrast change of brain glioma in vivo following administration of Tf-SPIONs owing to the larger accumulation of Tf-SPIONs in the cytoplasm of brain glioma.