Coordinatively Unsaturated Fe³⁺ Based Activatable Probes for Enhanced MRI and Therapy of Tumors

Abstract

Exogenous Fe III can be used for cancer magnetic resonance (MR) imaging and potentially for cancer treatment by aferroptosis pathway or photothermal ablation. To achieve this,effective and accurate delivery of Fe III to cancerous sites is critical, requiring ab alance of release kinetics of Fe 3+ in tumorous and normal tissues.An anoprobe is described consisting of upconversion luminescence (UCL) nanoparticles as ac ore and ac oordinatively unsaturated Fe III -containing Fe 3+ /gallic acid complex as as hell. Owing to the introduction of an unsaturated coordination structure,Fe III in the nanoprobe can be released only in the tumor microenvironment in response to the lightly acidic pH. The multiple UCLs are used for quantitatively visualizing the release of Fe 3+ in vivo,whilst the release resultant serves as ap hotothermal agent. This nanoprobe exhibited ligand-free tumor targeting ability,a ctivatable MR imaging performance,and efficacious therapeutic effects against tumors in vivo.

Ferroptosis: Final destination for cancer?

“…To specifically release iron to tumour tissues, one team developed a nanoprobe that consisting of upconversion luminescence (UCL) nanoparticles as a core and a coordinated Fe 3+ /gallic acid complex as a shell. This nanoprobe can release Fe 3+ only in tumour lesions in response to the lightly acidic tumour pH and thus triggered ferroptosis . Magnetosomes can also be iron carriers.…”

“…This nanoprobe can release Fe 3+ only in tumour lesions in response to the lightly acidic tumour pH and thus triggered ferroptosis. 108 Magnetosomes can also be iron carriers.…”

Designing highly stable ferrous selenide-black phosphorus nanosheets heteronanostructure via P-Se bond for MRI-guided photothermal therapy

“…Fe and Se belong to biofriendly elements [ 45 ]. Fe-containing nanoparticles have been widely studied in MRI [ 46 – 48 ]. FeSe 2 , as a crucial class of transition metal dichalcogenide, has attracted intensive interest because of its excellent magnetic properties [ 49 ], good electrical conductivity [ 50 ] and high absorbance in the near-infrared (NIR) region [ 51 ].…”

Semiconducting polymer nanoparticles for multimodal biophotonics

“…We synthesized the first semiconducting nanozyme (HSN) based on the complexation of an organic semiconducting polymer (pTBCB-PEG) and Fe 2+ for NIR-II PA imaging guided photothermal ferrotherapy (Figure 7.1a). Different from ordinary iron delivery systems (such as phenolic acid 337,344 , oxidized starch 371 , leukocyte membrane 338 and promoted self-degradation to tiny fragments for increased intratumoral penetration.…”

“…Specifically, kinetics studies indicate that Fenton reaction rate is enhanced by up to 4-fold upon increasing the temperature from 20 to 50 ℃ 343 . Thereby, PTT is promising to promote intratumoral Fenton reaction efficiency during ferrotherapy 344 . However, nanoagents that synergize NIR-II photothermal effect to augment ferro-therapeutic effect have been rarely reported 345 .…”