Dual-modal Imaging Of Perfluorohexane-loaded Nanoparticles Of Perfluorohexane Nanoparticles Coated With Iron And Tannic Acid

PART? PREPARATION AND CHARACTERIZATION OF PERFLUOROHEXANE-LOADED NANOPARTICLES ENCAPSULATED WITH IRON TANNIC CHARACTERIZATION DETECTIONobjective1.To prepare the nanoparticles using polylactic acid?PLGA?as shell,packaging Fe III-tannic acid?Fe IIITA?,containing perfluorohexane?PFH?as the core.2.To detect the characterization of Fe^?TA/PLGA/PFH nanoparticlesMethod1.Using the double emulsion method,preparation of PFH PLGA nanoparticles,with tannic acid?TA-Fe III?package PFH/PLGA nanoparticles,preparation of Fe III TA/PLGA/PFH nanoparticles.2.The size and dispersibility of Fe^?TA/PLGA/PFH nanoparticles were observed by optical microscope,and the size,distribution and potential size of Fe III TA/PLGA/PFH nanoparticles were examined by Malvern particle size meter.The structure of PLGA/PFH nanoparticles and Fe^?TA/PLGA/PFH nanoparticles were analyzed by transmission electron microscopy.Result1.Fe^?TA/PLGA/PFH nanoparticles were prepared,and the Fe IITA/PLGA/PFH nanoparticles were black-purple dissolved in deionized water.2.The Fe^?TA/PLGA/PFH nanoparticles are spherical structure with uniform size and good dispersion observed under light microscopy.The particle size of the nanoparticles is?229.4±37.94?nm,the polymer dispersion index?Pd I: 0.326?,the potential is?-17.6 ± 7.64?m V.The PLGA/PFH nanoparticles were observed to be black spherical under transmission electron microscopy,while the Fe^?TA/PLGA/PFH nanoparticles were intermediate gray white and peripheral black spherical.conclusion Fe^?TA/PLGA/PFH nanoparticles encapsulated with iron tannate was successfully prepared.The characterization of Fe^?TA/PLGA/PFH nanoparticles was examined,which were spherical,uniform in size and well dispersed.PHOTOTHERMAL EFFECT,PHASE TRANSITION AND DUAL MODE IMAGING OF NANOPARTICLES COATED WITH IRON TANNIC.objective1.To detect the photothermal effect of Fe^?TA/PLGA/PFH nanoparticles in vitro.2.To detect the phase transition of Fe^?TA/PLGA/PFH nanoparticles and the photoacoustic/ultrasound dual-modality imaging.Method1.The Fe^?TA/PLGA/PFH nanoparticles were grouped according to different concentrations,and each group was irradiated by 660 nm?0.5 W?laser for 5 min,with PBS as the control group.The temperature changes in each group was detected by thermal imager.Fe IITA/PLGA/PFH nanoparticles with the same concentration were irradiated with different laser intensity for 5 min,and PBS was used as the control group.The temperature changes in each group were detected by thermal imager.2.Different concentrations of Fe^?TA/PLGA/PFH nanoparticles were used to detect the photoacoustic signals of each group by photoacoustic imager,and the signal intensity of each group was analyzed.3.Fe^?TA/PLGA/PFH nanoparticle with different concentrations were irradiated with 660 laser?0.5W?for 5 minutes,and PBS was used as control group.The imaging effect was analyzed by ultrasonic diagnostic instrument.And irradiated by 660 laser?0.5W?Fe III TA/PLGA/PFH nanoparticles with a concentration of 0.25g/L for 5min,which were detected every 1min.PBS was the control group,and the imaging effect was analyzed by an ultrasound diagnostic instrument.At the same time,the phase transition was observed under a light microscope.Result1.Quantitative analysis of photothermal effect shows that the temperature and nanoparticle concentration of Fe^?TA/PLGA/PFH nanoparticles were positively correlated after 5minutes laser irradiation,and it was also observed that the speed and amplitude of temperature rise were correlated with the nanoparticle concentration,and the higher the temperature rise,the faster the concentration was.The correlation between temperature and concentration at 5 min was quantitatively analyzed,and the results showed that there was a positive correlation between them?R²=0.8486,P < 0.05?,while the temperature of the control group did not increase.With different power?0-1W?laser irradiation concentration of0.25g/L Fe^?TA/PLGA/PFH nanoparticles for 5minutes,it was observed that the speed and amplitude of temperature rise were related to laser irradiation power,and the higher the power,the faster the temperature rise.The photothermal maps of each group were observed for 5 min,and the correlation between temperature and power at 5 min was quantitatively analyzed.2.Analyzing the relationship between nanoparticle concentration and photoacoustic signal intensity,we found that the photoacoustic signal intensity increased with the increase of nanoparticle concentration,and the relationship between the two was positively correlated?R² = 0.9978,P <0.05?.3.To detect the relationship between nanometer concentration and ultrasound signal intensity,obvious signal enhancement can be observed in laser irradiation,B mode and Contrast-enhanced ultrasound?CEUS?mode.Quantitative analysis showed that the higher the concentration of nanoparticles,the stronger the B-mode signal,the positive correlation between them?R² = 0.8465,P < 0.05?,and the stronger the CEUS mode signal,and the positive correlation between them?r2 = 0.9363,P < 0.05?.Quantitative analysis of the relationship between laser irradiation duration and ultrasound signal intensity showed that with the increase of time,both B mode and contrast mode could be observed to increase the signal intensity significantly.Quantitative analysis of the change of signal intensity showed that with the increase of nanoparticle concentration,the stronger the B mode signal,the positive correlation between the two?R² =0.991,P < 0.05?.At the same time,the stronger the CEUS mode signal,the positive correlation between the two?R² = 0.992,P < 0.05?.The phase transition of nanoparticles was observed under light microscope.With the prolongation of irradiation time,the phase transition nanoparticles increased,and a large number of microbubbles were observed under light microscope.conclusion1.Fe^?TA/PLGA/PFH nanoparticles have good photothermal effect.2.Fe^?TA/PLGA/PFH nanoparticles have good phase transition ability and photoacoustic/ultrasound dual-mode imaging ability.PART? THE IN VIVO DISTRIBUTION AND DUAL MODE IMAGING OF THE NANOPARTICLESobjective1.To detect the distribution and metabolism of Fe^?TA/PLGA/PFH nanoparticles2.To evaluate the ability of photoacoustic/ultrasonic dual-mode imaging in vivo of Fe IIITA/PLGA / PFH nanoparticles.Method1.Construction of Y79 nude mice model: human Y79 cells in logarithmic phase were digested with trypsin and washed by centrifugation?1000 rpm × 5 min?.Y79 cells were resuspended with normal saline and inoculated subcutaneously on the right back of nude mice with the standard of 1×106 cells /100?L.Nude mice were fed in standard IVC system.The living condition and tumor condition of nude mice were observed regularly,and the follow-up study was started when the tumor grew to about 0.5cm32.The in vivo distribution of Fe^?TA/PLGA/PFH nanoparticles was measured by a multifunctional in vivo fluorometer.The nude mice were randomly divided into two groups,which were injected with Fe^?TA/PLGA/PFH nanoparticles and PBS;isoflurane After 24 hours,the brain,heart,lung,kidney,liver and tumor of the nude mice were dissected and separated,and then imaged again3.Photoacoustic imaging of Fe^?TA/PLGA/PFH nanoparticles in vivo The nude mice were randomly divided into two groups?n = 3?.Then the nude mice were anesthetized by intraperitoneal injection?1%Pentobarbital Sodium Solution 0.1ml / 20g?,placed in the photoacoustic imager,and observed the situation before the injection of nanoparticles in the tumor area.Fe^?TA/PLGA/PFH nanoparticles and PBS were injected into the tail vein of nude mice respectively.At different time points,the photoacoustic images?2h,4h,8h,12 h,24h,48h?of tumor sites were observed and copied,and the data were analyzed with the software of photoacoustic instrument.4.In vivo ultrasound imaging of 4 Fe^?TA/PLGA/PFH nanoparticles The tumor bearing nude mice were randomly divided into two groups?n=3?.Ultrasound signals of B mode and contrast mode were collected in PBS control group before laser irradiation and 5 minutes?2w/cm2?after laser irradiation.In the experimental group,24 hours after injection of Fe^?TA/PLGA/PFH nanoparticles,ultrasound signals of B mode and contrast mode were collected before and after 5 minutes?2w/cm2?of continuous laser irradiation of tumor area.Result1.After the injection of Fe^?TA/PLGA/PFH nanoparticles,the fluorescence signals?2,4,6,8,12,24,48h?were recorded respectively.It was found that the fluorescence signal intensity of tumor site increased gradually,and the fluorescence signal could still be detected at 48 h.2.Two hours after the injection of Fe IIITA/ PLGA / PFH nanoparticles,the photoacoustic signal intensity in the tumor area was significantly higher than that in the control group?P < 0.05?.The photoacoustic signal reached the maximum value 24 hours after injection.48 hours after injection,the photoacoustic signal value decreased.3.In contrast mode and B mode,there was no significant difference between the PBS control group and the PBS control group before and after infrared laser irradiation of tumor site?P > 0.05?.24 hours after the injection of Fe IIITA/ PLGA / PFH nanoparticles,the ultrasound signal of tumor site in contrast mode and B mode was significantly enhanced?P <0.05?.conclusion1.Fe IIITA/ PLGA / PFH nanoparticles can accumulate in tumor area,and the peak time is 24 hours,2.Fe^?TA/PLGA/PFH nanoparticles have good in vivo photoacoustic /ultrasound imaging ability.