These NGs change in size and have hydrophilic/hydrophobic properties at different in vivo environments, circulate in blood for a longer time compared with bared MNPs functionalized with Cy5.5-labeled lactoferrin, and can specifically accumulate in glioma tissues through the combination of the active targeting ability of lactoferrin and the enhanced passive targeting ability provided by the pH/temperature sensitivities of the nanogels. Here, LTF is linked to glioma.