Studies On Synthesis And Properties Of Layered Double Hydroxides Intercalated With Drugs

Layered materials are a class of compounds with special structure and function, inwhich Layered double hydroxides as an anionic layered material. Due to its specialstructure arising versatility, recent years, it becomes one of the hot study in developedcountries. Researchers have done a lot of work about the traditional functionalmaterials such as the preparation methods and their application in the field of drug release.Therefore, this issue has great theoretical and practical significance.In this paper, two different preparation methods were used to make the organic drugsnorfloxacin and ibuprofen intercalate into Layered double hydroxide. At the same time theselayered materials were given magnetic targeting properties and fluorescence properties. Weprepared a series of functional organic-inorganic composite materials which have a broadapplication prospect. Specific studies are as follows:Firstly, using ion-exchange method successfully prepared the broad-spectrumantibacterial drug norfloxacin intercalated into the Zn-Al LDHs composite materials.Experiments were carried out under the two conditions at the pH of9,10. From XRD patternswe know that （003） plane diffraction peak shift to low angle of2θ, under the pH of9, d003value increased from0.88nm to1.11nm, at the pH of10, d003value increased from0.88nmto1.31nm. At the same time the arrangement of norfloxacin molecules in the interlayer ofZn-Al LDHs has been given with the form of three-dimensional structure diagram. Finally,these intercalation materials were carried out with drug release experiment which showed thatthey all had good release properties.Secondly, using ion exchange method successfully synthesized ibuprofen intercalatedEu3+doped magnetic and luminescent Zn-Al LDHs organic-inorganic composite materials.XRD results showed d003value increased from0.88nm to1.09nm, combined with infraredspectra we know that ibuprofen successfully intercalated into the interlayer of Layereddouble hydroxides. A probable morphology of ibuprofen molecules in the interlayer ofLayered double hydroxides was proved out that monolayer ibuprofen molecules arrange asthe short axis parallel to the LDHs layers. Thermal analysis showed the sample had goodthermal stability, Adding the external magnetic field nearby the sample solution, proved thatthe sample has magnetic properties. Fluorescence spectra showed samples at590nm,614nm, 647nm had Eu³⁺5D0-⁷FJ（J=1,2,3） characteristic emission, Eu3+successful replaced withcationic of hydrotalcite layers, incorporation into the lattice of hydrotalcite layers. Finally, thesample and its physical mixture were carried out in simulated body fluid release, the resultshowed that the sample had a slow release characteristics, however, physical mixture did nothave this feature.Ibuprofen intercalated Sm3+doped magnetic and luminescent Mg-Al, Zn-Al LDHsorganic-inorganic composite materials were successfully synthesized by co-precipitationmethod.. XRD results showed that their d003value increased from0.78nm to2.35nm and1.01nm, respectively. Combined with their infrared spectra we know that ibuprofen havebeen successfully intercalated into the interlayer of Mg-Al, Zn-Al LDHs. Thermal analysisdata showed that compared with the original drug ibuprofen were of high thermal stability andthe thermal decomposition temperature shift to higher temperatures. From the arrangement ofibuprofen molecules in Mg-Al, Zn-Al LDHs we found that they were in the hydrotalcite layer,respectively with monolayer arrange as the short axis parallel to the LDH layers and doublelayer alternating arrange as the long axis parallel to the LDHs layers. Put these two samplesolutions nearby the magnetic field and good magnetic properties could be found.Fluorescence spectroscopy at the682nm appearing Sm³⁺⁴G_5/2-⁶H_9/2transition, shown theyhad light-emitting properties. From drug release experiments we found they had the feature ofslow release, sustained release for up to ten hours. In summary, the preparation of Sm3+dopedwith magnetic and fluorescent properties of ibuprofen intercalated Mg-Al, Zn-Al hydrotalciteorganic-inorganic composite materials have wide application field in magnetic targeting drugdelivery and fluorescent probes.