Photodynamic Therapy with Targeted Release of Boron-Dipyrromethene Dye from Cobalt(III) Prodrugs in Red Light.

Boron-dipyrromethene (BODIPY) dyes are promising photosensitizers for cellular imaging and photodynamic therapy (PDT) owing to their excellent photophysical properties and the synthetically tunable core. Metalation provides a convenient way to overcome the drawbacks arising from their low aqueous solubility. New photo-/redox-responsive Co(III) prodrug chaperones are developed as anticancer PDT agents for efficient cellular delivery of red-light-active BODIPY dyes. The photobiological activity of heteroleptic Co(III) complexes derived from tris(2-pyridylmethyl)amine (TPA) and acetylacetone-conjugated PEGylated distyryl BODIPY (HL1) or its dibromo analogue (HL2), [CoIII(TPA)(L1/L2)](ClO4)2 (1 and 2), are investigated. The Co(III)/Co(II) redox potential is tuned using the Co(III)-TPA scaffold. Complex 1 displays the in vitro release of BODIPY on red light irradiation. Complex 2, having good singlet oxygen quantum yield (ΦΔ âˆ¼ 0.28 in DMSO), demonstrates submicromolar photocytotoxicity to HeLa cancer cells (IC50 ≈ 0.23 µM) while being less toxic to HPL1D normal cells in red light. Cellular imaging using the emissive complex 1 shows mitochondrial localization and significant penetration into the HeLa tumor spheroids. Complex 2 shows supercoiled DNA photocleavage activity and apoptotic cell death through phototriggered generation of reactive oxygen species. The Co(III)-BODIPY prodrug conjugates exemplify new type of phototherapeutic agents with better efficacy than the organic dyes alone in the phototherapeutic window.

Isolation, characterization, and multimodal evaluation of novel glycolipid biosurfactant derived from Bacillus species: A promising Staphylococcus aureus tyrosyl-tRNA synthetase inhibitor through molecular docking and MD simulations.

Glycolipid-based biosurfactants (BSs), known for their intriguing and diverse properties, represent a largely uncharted territory in the realm of potential biomedical applications. This field holds great promise yet remains largely unexplored. This investigation provides new insights into the isolation, characterization, and comprehensive biomedical assessment of a novel glycolipid biosurfactant derived from Bacillus species, meeting the growing demand for understanding its multifaceted impact on various biomedical issues. Within this framework, two glycolipids, BG2A and BG2B, emerged as the most proficient strains in biosurfactant (BS) production. The biosurfactants (BSs) ascertained as glycolipids via thin layer chromatography (TLC) exhibited antimicrobial activity against S. aureus and E. coli. Both isolates exhibited anticancer effects against cervical carcinoma cells and demonstrated significant anti-biofilm activity against V. cholerae. Moreover, molecular docking and molecular dynamics (MD) simulations were employed to explore their antimicrobial resistance properties against Tyrosyl-tRNA synthetase (TyrRS) of Staphylococcus aureus, a well-annotated molecular target. Characterization and interpretation using Fourier transform infrared spectroscopy (FTIR) and nuclear magnetic resonance spectroscopy (1H and 13C NMR) confirmed that the BSs produced by each strain were glycolipids. These findings suggest that the isolated BSs can serve as effective agents with antibiofilm, antimicrobial, antioxidant, and anticancer properties, in addition to their considerable antibacterial resistance attributes.