Cerenkov luminescence excited fluorescence tomography based on rare earth nanoparticles / 中华核医学与分子影像杂志

ABSTRACT

Objective Using Cerenkov radiation energy transfer (CRET) effect of rare earth nanoparticles (RENPs) to enhance and convert Cerenkov luminescence into Cerenkov luminescence excited fluorescence,and to compare the accuracy of Cerenkov luminescence tomography (CLT) and Cerenkov luminescence excited fluorescence tomography (CLFT).Methods 68Ga (0.74 MBq) was used to respectively excite Y2O3 ∶Eu3+,Er2O3 and Eu2O3(10 mg/ml).Various radioactivities of 68Ga (3.70,1.85,0.92,0.46,0.23 MBq) were used to respectively excite Y2O3 ∶Eu3+ with a fixed concentration (10 mg/ml).A fixed radioactivity of 68Ga (3.70 MBq) was used to excite Y2O3 ∶Eu3+ with different concentrations (10.0,5.0,2.5,1.2,0.6 mg/ml) in order to find the relationships between the optical intensity and the radioactivity of 68Ga or the concentration of Y2O3 ∶Eu3+.Polyethylene tubes containing 68Ga (0.74 MBq) and 68Ga (0.74 MBq) +Y2O3 ∶Eu3+(1 mg) were respectively implanted into two nude mice,then PET/CT and optical imaging were acquired.Three-dimensional reconstruction was proceeded.One-way analysis of variance,two-sample t test,linear correlation analysis were used for data analysis.Results Y2O3 ∶Eu3+ could significantly and stably enhance the Cerenkov optical signal (F=53.35,q =17.03,P＜0.001).The enhanced optical signal intensity had linear relationships with the radioactivity of 68Ga or the concentration of Y2O3 ∶Eu3+(r values0.99and 0.93).Three-dimensional reconstruction result showed that CLFT had significantly higher similarity than CLT (0.43±0.14 vs 0.16±0.06,t =5.090,P＜0.05).Conclusion CLFT could reflect the distribution of radiopharmaceuticals more precisely than CLT,and therefore might have potential in biologic optical imaging.