The Synthesis And Application Of Rare Earth MOFs With Both Fluorescence And Drug Delivery Properties

Cancer is an of mortality factors which threats human health. As a conventionalstrategy for cancer treatment, the chemotherapy has many unavoidable restrictions.Therefore, seeking novel and effective cancer treatment is a long-term challenge forbioscientists. With the rapid development of nanotechnology, the emergence ofnano-drug carrier has provided many unparalleled advantages over traditionalchemotherapy and it opens up new way to treat cancer. Developing a nontoxic,effective nano-drug carriers used in vivo is attracting wide attentions. Metal-organicframeworks (MOFs), a novel porous materials, show great potential in the field ofnano-drug carriers. Herein we mainly investigate the nano-drug carriers possessingthe functions of high drug-loading, controllable release and double functionalimaging on the basis of rare earth MOFs materials.Firstly, we synthesized the rare earth MOFs materials from rare metal Eu andcarboxyl species under solvothermal conditions. The obtained material combinedmerits of the higher porosity of MOFs and excellent imaging ability of rare element,endowing it to be the best candidates as nano-drug carriers potentially. Throughtuning the size and morphology, we have obtained rod-shaped MOFs materials,Eu(BTC) with an average diameter below200nm. Then, we activated Eu(BTC) byEDC/NHS reaction and modified it with PEG to improve its biocompatibility andstability in bio-environment. Secondly, we chose doxorubicin hydrochloride (DOX)as a model drug and tested the performance of the as-prepared Eu(BTC)nanoparticles as nano-drug carriers. Mixing Eu(BTC) nanoparticles powder withDOX solution under rapid stirring can make Eu(BTC) nanoparticle load DOX. Wehave achieved the60%loading efficiency and97%of encapsulation efficiency ofEu(BTC) nanoparticles, which is much higher than any reported value in this area.Thirdly, we investigated the drug-releasing properties of Eu(BTC) nanoparticleswith loading DOX at four pH values (2,5,6and7). The results showed that pH hadplayed an important role in releasing rate and the maximum cumulative releasingrate. The releasing rate was faster and the maximum cumulative release rate ishigher at lower pH. The reason may be that DOX does not adsorb simply in thechannels of Eu(BTC) nanoparticles but coordinates with the unsaturated sites of Euand this kind of coordination is significantly influenced by pH values. Finally, wedemonstrated that the as-prepared Eu(BTC) nanoparticles, compared with free drugsthrough cell growth inhibition experiment, exhibit some extent of release andprevent burst effect and prolong the duration in vivo of drugs. We have found that Eu(BTC) nanoparticles have potential imaging ability in vivo by using laserconfocal microscopy (LCMS) and living imaging system.Multi-functional nano-drug carriers for cancer treatment and diagnosis exhibitgreat research value and potential applications. The as-prepared Eu(BTC)nanoparticles in this work are not mature yet, but it shows lots of advantages, suchas easily accessible raw materials, simple synthesis conditions, easily modifying andgood biocompatibility. Moreover, the carrier itself possesses multiple functions, andit can be reformed according to specific requirements under simple approach. Inbrief, Eu(BTC) nanoparticles are kind of nano-drug carriers with great potential.