Synthesis and In Vitro Studies of a Gd(DOTA)-Porphyrin Conjugate for Combined MRI and Photodynamic Treatment.
Sébastien JenniFrédéric BolzeCélia S BonnetAgnès PallierAngélique SourÉva TóthBarbara VenturaValérie HeitzPublished in: Inorganic chemistry (2020)
With the aim of developing new molecular theranostic agents, a π-extended Zn(II) porphyrin as photosensitizer for photodynamic therapy (PDT) linked to two GdDOTA-type complexes for magnetic resonance imaging (MRI) detection was synthesized. The relaxivity studies revealed a much higher relaxivity value per Gd ion for this medium sized molecule (19.32 mM-1 s-1 at 20 MHz and 298 K) compared to clinical contrast agents-a value which strongly increases in the presence of bovine serum albumin, reaching 25.22 mM-1 s-1. Moreover, the photophysical studies showed the strong ability of the molecule to absorb light in the deep red (670 nm, ε ≈ 60000 M-1 cm-1) and in the near-infrared following two-photon excitation (920 nm, σ2 ≈ 650 GM). The conjugate is also able to generate singlet oxygen, with a quantum yield of 0.58 in DMSO. Promising results were obtained in cellular studies, demonstrating that the conjugate is internalized in HeLa cells at micromolar concentration and leads to 70% of cell death following 30 min irradiation at 660 nm. These results confirm the potential of the designed molecule as an imaging and therapeutic agent.
Keyphrases
- photodynamic therapy
- magnetic resonance imaging
- fluorescence imaging
- cell death
- contrast enhanced
- case control
- cell cycle arrest
- cancer therapy
- induced apoptosis
- magnetic resonance
- diffusion weighted imaging
- computed tomography
- molecular dynamics
- heavy metals
- single cell
- risk assessment
- signaling pathway
- combination therapy
- pet imaging
- replacement therapy
- monte carlo