Synthesis and preclinical evaluation of [¹⁸F]AlF-NOTA-Glc-Folate as a novel folate-receptor-targeted PET tracer

A novel ¹⁸F-labeled radiotracer ([¹⁸F]AlF-NOTA-Glc-Folate) modified with a hydrophilic linker (-Glc-) was developed for PET imaging of folate-receptor-positive tumors. [¹⁸F]AlF-NOTA-Glc-Folate was manually synthesized within 30 min with high radiochemical yield and radiochemical purity. Cellular studies exhibited that [¹⁸F]AlF-NOTA-Glc-Folate had a high specificity and affinity for the folate-receptor. Biodistribution and micro-PET imaging results showed proper uptake of [¹⁸F]AlF-NOTA-Glc-Folate in tumors, as well as low uptake and rapid clearance in most normal organs, except for the kidney. [¹⁸F]AlF-NOTA-Glc-Folate seems to be a potential radiotracer for PET imaging of tumors with folate-receptor expression.