Preparation of 68Ga-labelled DOTA-peptides using a manual labelling approach for small-animal PET imaging

68Ga-DOTA-peptides are a promising PET radiotracers used in the detection of different tumours types due to their ability for binding specifically receptors overexpressed in these. Furthermore, 68Ga can be produced by a 68Ge/68Ga generator on site which is a very good alternative to cyclotron-based PET isotopes. Here, we describe a manual labelling approach for the synthesis of 68Ga-labelled DOTA-peptides based on concentration and purification of the commercial 68Ga/68Ga generator eluate using an anion exchange-cartridge. 68Ga-DOTA-TATE was used to image a pheochromocytoma xenograft mouse model by a microPET/CT scanner. The method described provides satisfactory results, allowing the subsequent 68Ga use to label DOTA-peptides. The simplicity of the method along with its implementation reduced cost, makes it useful in preclinical PET studies.