Table 1 Overview of natural siderophores investigated for radiolabelling discussed in this review.

Enterobactin (ENTB)

Enterobacteriaceae spp. (such as Escherichia coli, Klebsiella pneumoniae, Salmonella enterica)

Staphylococcus aureus, Yersinia enterocolitica

SPECT: ⁶⁷Ga, ¹¹¹In PET: ⁶⁸Ga

⁶⁸Ga: Derivates demonstrate RE and moderate GITE

Microbial uptake and transport mechanisms, scaffold for radiopharmaceuticals, antimicrobial therapy

^{81,104,131,132}

Ferrioxamine B (FOX B; DFO-B)

Streptomyces pilosus

Pseudomonas aeruginosa, Staphylococcus aureus, Streptococcus agalactiae, Burkholderia multivorans

SPECT: ¹¹¹In PET: ⁶⁸Ga, ⁸⁹Zr

¹¹¹In: Combined RE and GITE, bone marrow uptake ⁶⁸Ga: Rapid RE, minimal retention in blood and other organs ⁸⁹Zr: similar profile as ⁶⁸Ga

Infection imaging, microbial uptake and transport mechanisms, scaffold for radiopharmaceuticals for targeted imaging

^44,47,49,71

Ferrioxamine E (FOX E)

Streptomyces spp., Erwinia spp., Pantoea spp., Ewingella spp., Hafnia spp., Pseudomonas stutzeri

Acinetobacter baumannii, Aspergillus fumigatus, Staphylococcus aureus

PET: ⁶⁸Ga, ⁸⁹Zr

⁶⁸Ga: Rapid RE, moderate uptake in GIT, low blood values ⁸⁹Zr: predominant GITE, minimal retention in blood;

Infection imaging, microbial uptake and transport mechanisms

^39,47,85,133

Ferrirhodin (FRH)

Aspergillus vesicolor, Aspergillus nidulans, Aspergillus oryzae, Botrytis cinerea, Fusarium sacchari

Staphylococcus aureus, Klebsiella pneumoniae, Pseudomonas aeruginosa

PET: ⁶⁸Ga

⁶⁸Ga: Mixed RE and GITE, moderate retention in blood 90 min p. inj., uptake in liver and lung

Microbial uptake and transport mechanisms

⁶¹

Ferrirubin (FR)

Aspergillus ochraceus

Acinetobacter baumannii, Staphylococcus aureus, Klebsiella pneumoniae, Pseudomonas aeruginosa, Burkholderia multivorans

PET: ⁶⁸Ga

⁶⁸Ga: RE excretion, no uptake in non-targeted organs

Infection imaging, microbial uptake and transport mechanisms

^50,61,85

Ornibactin (ORNB)

Burkholderia cepacia complex

Low uptake in Pseudomonas aeruginosa, Staphylococcus aureus

PET: ⁶⁸Ga

⁶⁸Ga: RE, minimal retention in blood and other organs

Infection imaging, microbial uptake and transport mechanisms

⁵⁰

Pyoverdines (PVDs)

Pseudomonas aeruginosa

---

PET: ⁶⁸Ga

⁶⁸Ga: Rapid RE, minimal retention in blood and other organs

Infection imaging, microbial uptake and transport mechanisms

⁴⁸

Salmochelin S4 (SAL S4)

Enterobacteriaceae spp.

Staphylococcus aureus, Bacteroides thetaiotaomicron

PET: ⁶⁸Ga

⁶⁸Ga: Rapid RE, minimal retention in blood and other organs

Microbial uptake and transport mechanisms, scaffold for radiopharmaceuticals for antimicrobial therapy

^{100,109,131,134}

Schizokinen (SKN)

Bacillus megaterium

Streptococcus epidermidis, Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa

PET: ⁶⁸Ga

⁶⁸Ga: Predominant RE, retention in blood, GIT and ovaries 60 min p. inj.

Infection imaging, microbial uptake and transport mechanisms

⁵¹

Yersiniabactin (YbT)

Yersinia pestis, Yersinia enterocolitica, Yersinia pseudotuberculosis, Enterobacteriaceae spp.

---

PET: ⁶⁴Cu

⁶⁴Cu: RE and GITE, moderate uptake in heart and lung

Infection imaging, microbial uptake and transport mechanisms

^98,135