New starch-based radiotracer for lung perfusion scintigraphy

• Published in: European journal of nuclear medicine and molecular imaging Vol. 37; no. 1; pp. 146 - 155
• Main Authors: Lacoeuille, Franck, Hindré, François, Denizot, Benoit, Bouchet, Francis, Legras, Pierre, Couturier, Olivier, Askiénazy, Serge, Benoit, Jean Pierre, Le Jeune, Jean Jacques
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer-Verlag 2010; Springer Nature B.V; Springer Verlag (Germany) [1976-....]
• Subjects: Animals; Cardiology; Drug Carriers - chemistry; Imaging; Isotope Labeling - methods; Life Sciences; Lung - diagnostic imaging; Lung - metabolism; Lungs; Male; Medical imaging; Medicine; Medicine & Public Health; Microscopy; Nuclear Medicine; Oncology; Original Article; Orthopedics; Particle Size; Pattern Recognition, Automated - methods; Perfusion Imaging - methods; Radioisotopes; Radiology; Radiopharmaceuticals - chemical synthesis; Radiopharmaceuticals - pharmacokinetics; Rats; Rats, Wistar; Reproducibility of Results; Sensitivity and Specificity; Starch - chemistry; Technetium - chemistry; Technetium - pharmacokinetics; Blood derivative; Starch; Perfusion scintigraphy; Microparticles; Tc-99m radiopharmaceutical; Orthopedics; Oncology; Nuclear Medicine; Cardiology; Imaging / Radiology
• ISSN: 1619-7070; 1619-7089
• DOI: 10.1007/s00259-009-1226-6

Purpose In order to avoid the microbiological risks linked to human serum albumin macroaggregates (MAA) used for lung perfusion scintigraphy, we developed a new starch-based Tc-99m potential radiopharmaceutical. Methods Microparticles were prepared from oxidised starch coupled to natural polyamine for Tc-99m complexation. Suspensions were formulated as ready-to-use kits for easy one-step labelling procedures. Results Particle-size analysis, electron microscopy, and confocal microscopy were performed for microparticle characterisation, and gave a typical size distribution ranging from 7 to 63 µm, with a homogenous population of spherical or oval-shaped microparticles. Radiochemical purity exceeded 95%, and was stable for at least 8 h. When challenged with histidine and human plasma, labelling was also stable. Dynamic scintigraphic acquisitions and biodistribution studies conducted on healthy Wistar rats showed a tracer accumulation with more than 80% of the ID in the lungs after 15 min. Conclusions With clinically significant characteristics such as a lung half-life of 3 h, a lung-to-vascular ratio of 900, and a lung-to-liver ratio of 90, starch-based microparticles exhibit all the qualities for an effective new lung perfusion agent.