Chinese Researchers Developing Anti-bacterial Ruthenium PSsFor what it's worth, Theralase demonstrated photodynamic inactivation of Staphylococcus aureus using TLD1411 and TLD1433 and green light (530 nm) back in 2013.
Photodynamic inactivation of Staphylococcus aureus and methicillin-resistant Staphylococcus aureus with Ru(II)-based type I/type II photosensitizers Yaxal Arenas, Susan Monro, Ge Shi, Arkady Mandel, Sherri McFarland, Lothar Lilge
The Chinese researchers are developing new anti-bacterial ruthenium compounds that are activated by long wavelengths (808 nm)
Long wavelength–emissive Ru(II) metallacycle–based photosensitizer assisting in vivo bacterial diagnosis and antibacterial treatment Yuling Xu, Chonglu Li, Xin Ma, Wei Tuo, Le Tu, Xiaopeng Li, Yan Sun, Peter J. Stang, and Yao Sun
August 1, 2022
Significance
Bacterial infection is the major risk to public health. Developing emissive metal–based photosensitizers against bacterial infections draws continued interest in biomedicine. The most important issue is extending the absorption and emission wavelengths of metal-based photosensitizers to ameliorate the efficiency of in vivo imaging and phototherapy. To address this, we rationally designed a long-wavelength–emissive ruthenium (II) metallacycle (herein referred to as 1) that has superior optical penetration (∼7 mm) and satisfactory reactive oxygen species–generation performance. Complex 1 has promising broad-spectrum antibacterial activity and low toxicity to mammalian cells. Moreover, 1 enables high-performance, in vivo, fluorescent imaging-guided phototherapy of Staphylococcus aureus–infected mice, with ignorable adverse effects, thus demonstrating that 1 could be a good platform for pathogen phototheranostics.
Abstract
Ruthenium (Ru) complexes are developed as latent emissive photosensitizers for cancer and pathogen photodiagnosis and therapy. Nevertheless, most existing Ru complexes are limited as photosensitizers in terms of short excitation and emission wavelengths. Herein, we present an emissive Ru(II) metallacycle (herein referred to as 1) that is excited by 808-nm laser and emits at a wavelength of ∼1,000 nm via coordination-driven self-assembly. Metallacycle 1 exhibits good optical penetration (∼7 mm) and satisfactory reactive oxygen species production properties. Furthermore, 1 shows broad-spectrum antibacterial activity (including against drug-resistant Escherichia coli) as well as low cytotoxicity to normal mammalian cells. In vivo studies reveal that 1 is employed in precise, second near-infrared biomedical window fluorescent imaging–guided, photo-triggered treatments in Staphylococcus aureus–infected mice models, with negligible side effects. This work thus broads the applications of supramolecular photosensitizers through the strategy of lengthening their wavelengths.