Potentiation Effect of Iodine Species on the Antimicrobial Capability of Surfaces Coated with Electroactive Phthalocyanines

The spreading of different infections can occur through direct contact with glass surfaces in commonly used areas. Incorporating the use of alternative therapies in these materials seems essential to reduce and also avoid bacterial resistance. In this work, the capability to kill microbes of glass surfaces coated with two electroactive metalated phthalocyanines (ZnPc-EDOT and CuPc-EDOT) is assessed. The results show that both of these materials are capable of producing reactive oxygen species; however, the polymer with Zn(II) (ZnPc-PEDOT) has a singlet oxygen quantum yield 8-fold higher than that of the Cu(II) containing analogue. This was reflected in the in vitro experiments where the effectiveness of the surfaces was tested in bacterial suspensions, monitoring single microbe inactivation upon attachment to the polymers, and eliminating mature biofilms. Furthermore, we evaluated the use of an inorganic salt (KI) to potentiate the photodynamic inactivation mediated by an electropolymerized surface. The addition of the salt improved the efficiency of phototherapy at least two times for both polymers; nevertheless, the material coated with ZnPc-PEDOT was the only one capable of eliminating >99.98% of the initial microbes loading under different circumstances.

Excited-State Charge Transfer in Covalently Functionalized MoS2 with a Zinc Phthalocyanine Donor-Acceptor Hybrid

The functionalization of MoS₂ is of paramount importance for tailoring its properties towards optoelectronic applications and unlocking its full potential. Zinc phthalocyanine (ZnPc) carrying an 1,2-dithiolane oxide linker was used to functionalize MoS₂ at defect sites located at the edges. The structure of ZnPc-MoS₂ was fully assessed by complementary spectroscopic, thermal, and microscopy imaging techniques. An energy-level diagram visualizing different photochemical events in ZnPc-MoS₂ was established and revealed a bidirectional electron transfer leading to a charge separated state ZnPc^.+ -MoS₂ ^.- . Markedly, evidence of the charge transfer in the hybrid material was demonstrated using fluorescence spectroelectrochemistry. Systematic studies performed by femtosecond transient absorption revealed the involvement of excitons generated in MoS₂ in promoting the charge transfer, while the transfer was also possible when ZnPc was excited, signifying their potential in light-energy-harvesting devices.

An anionic phthalocyanine decreases NRAS expression by breaking down its RNA G-quadruplex

Aberrant activation of RAS signalling pathways contributes to aggressive phenotypes of cancer cells. The RAS-targeted therapies for cancer, therefore, have been recognised to be effective; however, current developments on targeting RAS have not advanced due to structural features of the RAS protein. Here, we show that expression of NRAS, a major isoform of RAS, can be controlled by photo-irradiation with an anionic phthalocyanine, ZnAPC, targeting NRAS mRNA. In vitro experiments reveal that ZnAPC binds to a G-quadruplex-forming oligonucleotide derived from the 5'-untranslated region of NRAS mRNA even in the presence of excess double-stranded RNA, which is abundant in cells, resulting in selective cleavage of the target RNA's G-quadruplex upon photo-irradiation. In line with these results, upon photo-irradiation, ZnAPC decreases NRAS mRNA and NRAS expression and thus viability of cancer cells. These results indicate that ZnAPC may be a prominent photosensitiser for a molecularly targeted photodynamic therapy for cancer.

Synthesis of zincphthalocyanine-based conjugated microporous polymers with rigid-linker as novel and green heterogeneous photocatalysts

The novel zincphthalocyanine-based conjugated microporous polymers with rigid-linker (α-ZnPc-CMP and β-ZnPc-CMP) were synthesized by copolymerization of zinc phthalocyanine (ZnPc) and 4, 6-diaminoresorcinol dihydrochloride (DADHC). The α-ZnPc-CMP and β-ZnPc-CMP were utilized as heterogeneous photocatalysts to degrade Rhodamine B (RhB) in aqueous solution. It is the first time for MPc-based CMPs used as heterogeneous photocatalysts for photodegradation of RhB to date. The highly ordered skeletal alignment and two-dimensional open-channel structure of α-ZnPc-CMP and β-ZnPc-CMP not only solve the aggregation of ZnPc and enhance its photocatalytic activity, but also facilitate the recycling and avoid the secondary pollution. The chemical structures and morphologies of α-ZnPc-CMP and β-ZnPc-CMP were well characterized by Fourier transform infrared spectra (FT-IR), solid-state ¹³C nuclear magnetic resonance (¹³C NMR), scanning electron microscopy (SEM), N₂-sorption/ desorption and X-ray diffraction (XRD). The solubility experiments and thermogravimetric analysis (TGA) showed they have good chemical stability and recyclability. Furthermore, the photocatalytic tests indicated α-ZnPc-CMP and β-ZnPc-CMP have excellent photocatalytic performances for degradation of RhB (3 h, degraded 98 and 97.47%) in the presence of H₂O₂ under visible-light irradiation. All results reveal that α-ZnPc-CMP and β-ZnPc-CMP have great potential as photocatalysts on the degradation of organic dye contaminants. Moreover, the possible reaction mechanism of α-ZnPc-CMP and β-ZnPc-CMP as photocatalysts for the degradation of RhB is proposed.

A near-infrared organic photosensitizer for use in dye-sensitized photoelectrochemical water splitting

Dye-sensitized photoelectrochemical cells (DSPECs) composed of a new near-infrared BODIPY dye D1 that is co-deposited with a ruthenium water oxidation catalyst C1 have been fabricated. The devices at pH 7.2 showed an excellent Faradaic efficiency of H₂ production (65.8%) that was 5.4 times larger than that of a triphenylamine photosensitizer D2 and C1-coadsorbed cell.