Fluorescence Responsive Properties Of CeF₃ Nanocrystals/HPC-PAA Complex Nanogel And Its Drug Release Behavior

In recent years,rare earth nanocrystals have been used in various fields such as fluorescent probes and bioimaging because of their excellent fluorescent properties and stable chemical structure.The preparation of thermosensitive nanomaterials based on hydroxypropyl cellulose has the advantages of simple synthesis and no pollution to the environment.If two kinds of materials are combined,the new environmentally sensitive complex nanogel can be used in organism.In the object,it provides a theoretical basis for the study of new fluorescent nanomaterials.In this paper,a series of functional nanogels were synthesized by combining rare earth nanocrystals and HPC nanogels,and their drug loading and release properties were studied.The specific contents of this paper are as follows:?1?In this paper,using HPC as a template,non-saponified emulsion polymerization was used to prepare HPC-PAA nanogels,and then Ce?NO₃?₃ solution and NH₄F solution were added in order.Finally,Ce F₃ nanocrystals were prepared in HPC-PAA nanogels.The microstructure and properties of Ce F₃ nanocrystals/HPC-PAA nanogels were characterized by Fourier transform infrared?FTIR?,X-ray diffraction?XRD?,thermogravimetry?TG?,and transmission electron microscopy?TEM?.Fluorescence spectrum?PL?and UV-Vis spectrophotometer?UV-Vis?studied the temperature and p H sensitivity of nanogels.In addition,the drug loading and release behavior of nanogels was studied using Ibuprofen as a model drug.The results show that needle-like Ce F₃nanocrystals exist in nanogels,and the fluorescence intensity of nanogels is affected by changes in ambient temperature and p H.The fluorescence intensity of Ce F₃nanocrystals in the nanogel decreases with the increase of the concentration of Ibuprofen loaded in the nanogel,and the prolongation of the drug release time of the nanogel makes the fluorescence intensity of the nanogel gradually increase.?2?HPC-PAA/Eu?AA?₃Phen nanogels were synthesized by free-radical polymerization using hydroxypropylcellulose?HPC?,rare earth complexes?Eu?AA?₃Phen?and acrylic acid?AA?.Coupling of 1-?3-dimethylaminopropyl?-3-ethylcarbodiimide hydrochloride?EDC?,and the nanogel was modified with3-aminophenylboronic acid?3-PBA?.HPC-PAAPBA/Eu?AA?₃Phen nanogel with fluorescence response to temperature,p H and glucose was prepared.The infrared microscopy?FTIR?,transmission electron microscopy?TEM?,and dynamic light scattering?DLS?were used to characterize the microstructure of the nanogels.The fluorescence spectra were used to focus on the environmental temperature,p H and the stimulus-response performance of glucose.The results showed that the synthesized two nanogels were uniform in size and had good monodispersity.The temperature,p H value and glucose concentration had significant effects on the particle size and fluorescence emission intensity of the nanogels modified by PBA.