Sulfobutylether-β-cyclodextrin/5,10,15,20-tetrakis(1-methylpyridinium-4-yl)porphine nanoassemblies with sustained antimicrobial phototherapeutic action

摘要: Abstract Nowadays, novel less-expensive nanoformulations for in situ-controlled and safe delivery of photosensitisers (PSs) against opportunistic pathogens body-infections areas need to be developed. Antimicrobial photodynamic therapy (aPDT) is a promising approach treat bacterial infections that are recalcitrant antibiotics. In this paper, we propose the design characterization nanophototherapeutic based on trade cyclodextrin CAPTISOL® (sulfobutylether-beta-cyclodextrin, SBE-βCD) 5,10,15,20-tetrakis(1-methylpyridinium-4-yl)porphine tetrakis(p-toluenesulfonate) (TMPyP) fabricate efficient biocompatible systems aPDT. Spherical nanoassemblies about 360 nm CAPTISOL®/TMPyP supramolecular complexes with 1:1 stoichiometry apparent equilibrium binding constant (Kb ≅ 1.32 × 105 M−1) were prepared entrapment efficiency of ≅ 100% by simple mixing aqueous media freeze-drying. These have been characterized complementary spectroscopy microscopy techniques. Time resolved fluorescence pointed out strong interaction porphyrin monomer within (τ2 ≅ 11 ns an amount ca 90%) scarce self-aggregation porphyrins observed. Singlet oxygen comparative determination (ϕΔ CAPTISOL®/TMPyP = 0.58) assessed their potential. Release photostability studies carried under physiological conditions pointing role sustain release more than 2 weeks protect PS from photodegradation. Finally, photoantimicrobial activity vs free investigated Gram-negative P. aeruginosa, E. coli Gram-positive S. aureus. The proposed nanosystems able photokill both -negative cells similarly TMPyP at MBC90 = 6 µM 42 J/cm2 light dose. However, respect less selective biological sites, exhibit sustained properties higher thus optimizing PDT effect site action. results can open routes vivo translational nano(photo)drugs nanotheranostics expensive formulations CD PS.