Assessment of the biodistribution of an [18F]FDG‐loaded perfluorocarbon double emulsion using dynamic micro‐PET in rats. (24th April 2013)

• Record Type: Journal Article
• Authors: Fabiilli, Mario L.; Piert, Morand R.; Koeppe, Robert A.; Sherman, Phillip S.; Quesada, Carole A.; Kripfgans, Oliver D.
• Is Part Of: Contrast media & molecular imaging. Volume 8:Number 4(2013:Jul./Aug.)
• Page Start: 366
• Page End: 374
• Publication Date: 2013-04-24
• Subjects: micro‐PET -- biodistribution -- perfluorocarbon -- emulsion -- acoustic droplet vaporization -- ultrasound -- responsive agents; Diagnostic imaging -- Periodicals; Magnetic resonance imaging -- Periodicals; Contrast media (Diagnostic imaging) -- Periodicals; Contrast Media -- Periodicals; Diagnostic Imaging -- Periodicals; Substances de contraste -- Périodiques; Diagnostics moléculaires -- Périodiques; Imagerie médicale; Substance de contraste; Périodique électronique (Descripteur de forme); Ressource Internet (Descripteur de forme); 616.0754
• DOI: 10.1002/cmmi.1532
• Languages: English
• ISSNs: 1555-4309

Abstract

Abstract : Perfluorocarbon (PFC) double emulsions loaded with a water‐soluble, therapeutic agent can be triggered by ultrasound in a process known as acoustic droplet vaporization. Elucidating the stability and biodistribution of these sonosensitive vehicles and encapsulated agents is critical in developing targeted drug delivery strategies using ultrasound. [ 18 F]fluorodeoxyglucose (FDG) was encapsulated in a PFC double emulsion and the in vitro diffusion of FDG was assessed using a Franz diffusion cell. Using dynamic micro‐positron emission tomography and direct tissue sampling, the biodistribution of FDG administered as a solution (i.e. non‐emulsified) or as an emulsion was studied in Fisher 344 rats ( n = 6) bearing subcutaneous 9L gliosarcoma. Standardized uptake values (SUVs) and area under the curve of the SUV (AUCSUV ) of FDG were calculated for various tissues. The FDG flux from the emulsion decreased by up to a factor of 6.9 compared with the FDG solution. FDG uptake, calculated from the AUCSUV, decreased by 36% and 44% for brain and tumor, respectively, when comparing FDG solution vs FDG emulsion ( p < 0.01). Decreases in AUCSUV in highly metabolic tissues such as brain and tumor demonstrated retention of FDG within the double emulsion. No statistically significant differences in lung AUCSUV were observed, suggesting minimal accumulation of the emulsion in the pulmonary capillary bed. The liver AUCSUV increased by 356% for the FDG emulsion, thus indicating significant hepatic retention of the emulsion. Copyright © 2013 John Wiley & Sons, Ltd. Abstract : Perfluorocarbon (PFC) double emulsions of the form water‐in‐PFC‐in‐water (W1 /PFC/W2 ) can carry water‐soluble agents in the W1 phase, the release of which can be triggered by ultrasound in a process known as acoustic droplet vaporization. The biodistribution of [ 18 F]fluorodeoxyglucose (FDG), encapsulated in the sonosensitive emulsion, was studied in rats using dynamic micro‐PET imaging. Compared to non‐emulsified FDG, less FDG uptake was observed in brain and tumor tissue with emulsified FDG, indicating stable retention of FDG within the emulsion.