Gadolinium(III) Porphyrinoid Phototheranostics

Abstract

Molecular phototheranostics as an emerging field of modern precision medicine has recently attracted increasing research attention owing to non‐invasiveness, high precision, and controllable nature of light. In this work, we reported promising gadolinium (Gd3+) porphyrinoids as phototheranostic agents for magnetic resonance imaging (MRI) and photodynamic therapy (PDT). The synthesized Gd‐1‐4‐Glu featured with meso‐glycosylation and β‐lactonization to endow good biocompatibility and improved photophysical properties. In particular, β‐lactonization of glycosylated Gd3+ porphyrinoids substantially red‐shifted Q band absorption to near‐infrared (NIR) region and boosted generation of reactive oxygen species including 1O2, and some radical species that engaged in both type II and type I PDT pathways. In addition, the number and regioisomerism of β‐oxazolone moieties was observed to play an essential role in improving longitude relaxivity (r1) of Gd‐1‐4‐Glu of up to 4.3±0.2 mM−1s−1 by affecting environmental water exchange. Taking Gd‐4‐Glu as a promising complex, we further achieved real‐time T1‐weighted MRI and PDT on HeLa tumour mice in vivo, revealing the appealing potential of Gd3+ porphyrinoids in phototheranostics.

Chiral lanthanide hexaazamacrocycles for circularly polarized luminescence, high relaxivity and magnetic resonance imaging

“…Under this circumstance, polar groups will play a vital role in transmitting the relaxation. 50 For GBCAs with q > 0, the contribution of inner-sphere relaxation to r 1 should be considered. Theoretically, the greater the q value, the higher the inner-sphere relaxivity; however, more coordinated water molecules will greatly destroy the stability of chelates, increasing the risk of releasing toxic Gd( iii ) ions.…”

Lanthanide porphyrinoids as molecular theranostics

“…191 In 2022, the Zhang group reported glycosylated cis -( 74 )/ trans ( 75 )-Gd porphodilactones as ‘proof-of-concept’ dual modal MRI and PDT theranostic systems. 192 Owing to regioisomerism, the ostensibly related isomers showed different r 1 relaxivities (4.3 ± 0.2 mM −1 s −1 for 74 and 2.8 ± 0.2 mM −1 s −1 for 75 ) under 0.5 T, 37 °C. Of note, 75 exhibited substantial red-shifted absorption beyond 660 nm and robust generation of reactive oxygen species, including 1 O 2 and radicals (O 2 ˙ − and ˙OH), that engaged in both Type II and Type I PDT pathways.…”

Theranostics with photodynamic therapy for personalized medicine: to see and to treat

“…Recently, Jin et al reported the synthesis of a series of water-soluble Gd(III)-porphyrinoids ( 60a-c ), which showed suitability as new phototheranostics based on PDT and MRI. The designed compounds contained meso -glycosylation and β -lactonization features, to improve their photophysical properties, solubility and biocompatibility 119 . Hereby, compound 60c showed the best NIR light-harvesting properties, as well as a similar ROS generation and higher photostability than the clinical photosensitizer methylene blue, and was thus chosen for an in-depth investigation.…”