Radiolabelled porphyrins in nuclear medicine

Abstract

Amongst tumour-specific substances, hematoporphyrin and synthetic porphyrin derivatives have been widely investigated to identify and delineate neoplastic and malignant tissue. Whilst the tumour localization exhibited by selected porphyrin species has been exploited through photodynamic therapy, several examples of porphyrin derivatives with varied peripheral functionality have been radiolabelled with the aim of developing porphyrin-based nuclear imaging and therapeutic agents. In this review, we look at the approaches and advances in the preparation and uses of such radiolabelled agents for imaging and therapy.

Preparation and the biodistribution study of [131I]-5,10,15,20-tetrakis(4-hydroxyphenyl)porphyrin and 5-(4-aminophenyl)-10,15,20-triphenylporphyrin

“…This is related to their lipophilicity of 131 I-TPPOH (logP o/w = 0.192) and 131 I-TPPNH 2 (logP o/w = 0.418). High liver accumulation is common with lipophilic porphyrins, where the hepatobiliary excretion pathway is dominant [29]. The relatively high uptakes of 131 I-TPPOH in spleen (5.03 %ID/g) and lung (4.59 %ID/g), which is also often observed for lipophilic porphyrins [15], indicates that macrophages played an important role in the clearance of 131 I-TPPOH.…”

Protoporphyrin‐IX and Manganese Oxide Nanoparticles Encapsulated in Niosomes as Theranostic

“…The MnO nanoparticles have been revealed to act as the catalase‐like nanoenzyme to react with overexpressed hydrogen peroxide to produce oxygen molecules. Thus this could overcome tumor hypoxia and enhance the therapeutic efficacy of radiotherapy …”

“…Thus this could overcome tumor hypoxia and enhance the therapeutic efficacy of radiotherapy. [26] PP-IX has been selected as an appropriate intermediate for PDT due to its light-sensitive property. Besides, it is a good chelator for some metallic radionuclides, hence, it has been previously radiolabelled to construct porphyrin-based nuclear imaging and therapeutic agents.…”

“…Besides, it is a good chelator for some metallic radionuclides, hence, it has been previously radiolabelled to construct porphyrin-based nuclear imaging and therapeutic agents. [26][27][28] 69/71Ga/68Ga-PP-IX compounds have also been proposed as single targeted molecular entities with potential applications in non-simultaneous in vitro fluorescence microscopy and in vivo positron emission tomography (PET) imaging. [29] Additionally, PP-IX has more radiosensitizer effect for cancer cells than healthy cells during radiotherapy.…”

Chelating agents for radiolanthanides: Applications to imaging and therapy

“…The radiolabelling of porphyrins in nuclear medicine has been reviewed elsewhere, 94 highlighting the large number of metallo-radionuclides that have been investigated in this context, including 99m Tc, 57 Co, 64 Cu, 67 Ga, 68 Ga, 109 Pd, 111 In, 209 Pb and 213 Bi. The first metalloporphyrins based on lanthanides were synthesised in the 1970s 95 and were initially investigated as shift reagents in NMR.…”