Study Of LiGa₅O₈:Cr³⁺ Long Afterglow Nanomaterials Preparation And Biocompatibility

Near-infrared long-persistence materials can be widely used in biological imaging.Since it has the characteristics of non-obscured light/chemical stability,after surface modification.In this study,LiGa₅O₈:Cr³⁺were successfully prepared by sol-gel method and hydrothermal method using LiNO₃,Ga（NO₃）₃·9H₂O,Cr（NO₃）₃,citric acid and Tween 20 as raw materials.It was modified by PEG method,SiO₂method and PEG-SiO₂method to prepare long afterglow nanomaterials which can be applied in the field of bioimaging.LiGa₅O₈:Cr³⁺prepared by sol-gel method,when Cr³⁺doping concentration is 1.0%,citric acid ratio 1:2,calcination temperature 1373 K;LiGa₅O₈:Cr³⁺prepared by hydrothermal method,when citric acid ratio 7:1,hydrothermal temperature is 435 K,calcination temperature is 1373 K,the luminescence properties of the samples are the best.At this time,the particle size of the samples are 180 nm and 120 nm.The excitation peak positions are 420 nm and 608 nm,the emission peak position is 720 nm,and the emission time of near-infrared light can reach five minutes.By comparing the particle size and luminescence intensity of LiGa₅O₈:Cr³⁺,the LiGa₅O₈:Cr³⁺prepared by the hydrothermal method was determined in subsequent experiments.The surface of LiGa₅O₈:Cr³⁺was modified by two methods.The samples were tested by TEM,Zeta potential and infrared spectroscopy.The analysis showed that the three methods were successfully modified the LiGa₅O₈:Cr³⁺.The particle size of samples are 125 nm and 150 nm.Cytotoxicity,cell staining and cell imaging tests were performed on samples.The results showed that the cell viability of PEG-LGO:Cr@mSiO₂was still above 92%on the fifth day;the cell staining was consistent with the cytotoxicity results.The sample was excited and the sample emitted red light spots visible to the naked eye in the cells.It shows that the biocompatibility of the PEG-SiO₂modification method is the best among the two methods,and cell imaging is successfully achieved.Figure 57;Table 5;Reference 63...