Abstract
Erbium-doped zinc-aluminum layered double hydroxide (Er3+-doped ZnAl-LDH) with near-infrared emission has been studied as the delivery and release of the 5-fluorouracil (5-Fu) which was an anticancer drug. Compositional and structural analyses reveal that the 5-Fu has been successfully intercalated into the interlayer of Er3+-doped ZnAl-LDH, and the basal spacing of the Er3+-doped LDH varied from 8.78 to 14.32 Å after the intercalation of 5-Fu. The release of 5-Fu was controlled in simulated intestinal medium (phosphate buffer solutions with pH 7.4 and 37 ℃). The releasing behavior of 5-Fu showed an initial quick-release followed by a slow-release. What is more, the intercalation of 5-Fu into the Er3+-doped ZnAl-LDH greatly reduced the near-infrared emissions of the Er3+-doped ZnAl-LDH, whereas the near-infrared emissions were recovered after the release of 5-Fu. The change of near-infrared emissions may be a useful technique for marking the delivery and release of 5-Fu at specific sites. Therefore, the Er3+-doped ZnAl-LDH with cheapness, non-toxicity, bio-compatibility, and little damage to biological tissue, may be a promising drug delivery system with marking or labeling function.