title: Fabrication of a nano-drug delivery system based on layered rare-earth hydroxides integrating drug-loading and fluorescence properties.
abstract: We demonstrate the first example of intercalation of naproxen (abbr. NPX) into layered europium hydroxide (LEuH) and investigate the structure, chemical composition, thermostability, morphology, luminescence properties, cytotoxic effect, and controlled-release behaviors. Different deprotonation degrees lead to NPX-LEuH composites with diverse structures (horizontal or vertical arrangement), and the thermal stability of organics is enhanced after intercalation. The Eu(3+) luminescence in NPX-LEuH composites is enhanced, especially for the NPX-LEuH-1 : 0.5 composite. The content of naproxen in the intercalation material can be confirmed by HPLC. The cytotoxic effect of LEuH is observed with a sulforhodamine B (SRB) colorimetric assay, which reveals that the LEuH has low cytotoxic effects on most cells. In addition, the NPX-LEuH nanocomposites can control the release of NPX in Na2HPO4-NaH2PO4 buffer solution at pH 6.86 and 37 °C, and the complete release needs about 200 min. The release mechanism can be ascribed to the ion-exchange reaction between NPX and HPO4(2-)/H2PO4(-) in bulk solution. The ion-exchange velocity is fast at the beginning and slows down gradually with the exchange reaction. The construction of LRH composites with drug molecules provides a beneficial pathway for preparing a nano-drug delivery system based on LRHs integrating drug-loading and fluorescence properties.
authors.affiliation: Department of Chemical Engineering, Beijing Institute of Petrochemical Technology, Beijing 102617, China. guqingyang@bipt.edu.cn.
authors.forename: Qingyang
authors.initials: Q
authors.lastname: Gu
authors.affiliation: Department of Chemical Engineering, Beijing Institute of Petrochemical Technology, Beijing 102617, China. guqingyang@bipt.edu.cn.
authors.forename: Wen
authors.initials: W
authors.lastname: Chen
authors.affiliation: Department of Chemical Engineering, Beijing Institute of Petrochemical Technology, Beijing 102617, China. guqingyang@bipt.edu.cn.
authors.forename: Fei
authors.initials: F
authors.lastname: Duan
authors.affiliation: Department of Chemical Engineering, Beijing Institute of Petrochemical Technology, Beijing 102617, China. guqingyang@bipt.edu.cn.
authors.forename: Ruijun
authors.initials: R
authors.lastname: Ju