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A photoactive analogue of cisplatin was synthesized with two arylazopyrazole ligands, able to undergo trans - cis / cis - trans photoisomerizations. The cis photoisomer showed a dark half-life of 9 days. The cytotoxicities of both photoisomers of the complex were determined in several cancer and normal cell lines and compared to that of cisplatin. The trans photoisomer of the complex was much more cytotoxic than both the cis photoisomer and cisplatin, and was more toxic for cancer (4T1) than for normal (NMuMG) murine breast cells. 4T1 cell death occurred through necrosis. Photoisomerization of the trans and cis photoisomers internalized by the 4T1 cells increased and decreased their viability, respectively. The cellular uptake of the trans photoisomer was stronger than that of both the cis photoisomer and cisplatin. Both photoisomers interacted with DNA faster than cisplatin. The trans photoisomer was bound stronger by bovine serum albumin and induced a greater decrease in cellular glutathione levels than the cis photoisomer.

We report herein the synthesis of aza-BODIPY substituted with 1,4-benzodioxane-6-yl substituents at 3,5 positions of the chromophore system. Both pyrrole rings of the aza-BODIPY in question were substituted with bromine atoms in order to induce highly desirable photophysical properties, such as highly populated excited triplet state (T 1 ) and long excited triplet-state lifetime (τ T ) of 21 μs. The photosensitized oxygenation of a model compounds, viz. DPBF, points to a high singlet oxygen and/or other ROS formation quantum yield of 0.42. The photosensitizer studied exhibited an absorption band within the so-called "therapeutic window", with λ abs 678 nm. As estimated by CV/DPV measurements the 1,4-benzodioxane-6-yl substituted aza-BODIPYs studied exhibited a multi-electron oxidations at a relatively low potentials (E ox ), pointing to the very good electron-donating properties of these molecules. High photostability and thermal stability was observed for all compounds studied. The good singlet oxygen quantum yield measured combined with an exceptional photostability makes this aza-BODIPY a promising candidate for applications such as photocatalysis and photodynamic therapy (PDT)., (© 2024 Wiley-VCH GmbH.)

Curcumin, a natural product with recognized antiviral properties, is limited in its application largely due to its poor solubility. This study presents the synthesis of water-soluble curcumin-poly(sodium 4-styrenesulfonate) (Cur-PSSNa n ) covalent conjugates. The antiflaviviral activity of conjugates was validated in vitro by using the Zika virus as a model. In the development of these water-soluble curcumin-containing derivatives, we used the macromolecules reported by us to also hamper viral infections. Mechanistic investigations indicated that the conjugates exhibited excellent stability and bioavailability. The curcumin and macromolecules in concerted action interact directly with virus particles and block their attachment to host cells, hampering the infection process.

The biological activity of polycations is usually associated with their biocidal properties. Their antibacterial features are well known, but in this work, observations on the antifungal properties of macromolecules obtained by methacrylamido propyl trimethyl ammonium chloride (MAPTAC) polymerization are presented. The results, not previously reported, make it possible to correlate antifungal properties directly with the structure of the macromolecule, in particular the molecular mass. The polymers described here have antifungal activity against some filamentous fungi. The strongest effect occurs for polymers with a mass of about 0.5 mDa which have confirmed activity against the multidrug-resistant species Scopulariopsis brevicaulis, Fusarium oxysporum, and Fusarium solani, as well as the dermatophytes Trichophyton mentagrophytes, Trichophyton rubrum, Trichophyton interdigitale, and Trichophyton tonsurans. In addition, this publication describes the effects of these macromolecular systems on serum and blood components and provides a preliminary assessment of toxicity on cell lines of skin-forming cells, i.e., fibroblasts and keratinocytes. Additionally, using a Franz diffusion chamber, a negligibly low transport of the active polymer through the skin was demonstrated, which is a desirable effect for externally applied antifungal drugs. IMPORTANCE Infectious diseases are a very big medical, social, and economic problem. Even before the COVID-19 pandemic, certain infections were among of the most common causes of death. The difficulties in the treatment of infectious diseases concern in particular fungal diseases, against which we have only a few classes of drugs represented by a few substances. The publication presents the preliminary results of the in vitro antifungal activity studies of four MAPTAC polymers on different fungal species and their cytotoxicity to human cells (fibroblasts and keratinocytes). The paper also compares these properties with analogous ones of two commonly used antifungal drugs, ciclopirox and terbinafine., Competing Interests: The authors declare no conflict of interest.

A series of poly(ethylene glycol)- block -poly(sodium 4-styrenesulfonate) (PEG- b -PSSNa) copolymers were synthesized, and their antiviral activity against Zika virus (ZIKV) was determined. The polymers inhibit ZIKV replication in vitro in mammalian cells at nontoxic concentrations. The mechanistic analysis revealed that the PEG- b- PSSNa copolymers interact directly with viral particles in a zipper-like mechanism, hindering their interaction with the permissive cell. The antiviral activity of the copolymers is well-correlated with the length of the PSSNa block, indicating that the copolymers' ionic blocks are biologically active. The blocks of PEG present in copolymers studied do not hinder that interaction. Considering the practical application of PEG- b -PSSNa and the electrostatic nature of the inhibition, the interaction between the copolymers and human serum albumin (HSA) was evaluated. The formation of PEG- b -PSSNa-HSA complexes in the form of negatively charged nanoparticles well-dispersed in buffer solution was observed. That observation is promising, given the possible practical application of the copolymers., Competing Interests: The authors declare no competing financial interest., (© 2023 The Authors. Published by American Chemical Society.)

New chemical structures with antifungal properties are highly desirable from the point of view of modern pharmaceutical science, especially due to the increasingly widespread instances of drug resistance in the case of these diseases. One way to solve this problem is to use polymeric drugs, widely described as biocidal, positively charged macromolecules. In this work, we present the synthesis of new cationic β-glucan derivatives that show selective antifungal activity and at the same time low toxicity toward animal and human cells. Two β-glucans isolated from oats and barley and modified using glycidyltrimethylammonium chloride were obtained and evaluated for biocidal properties on the cells of mammals and pathogenic fungi and bacteria. These compounds were found to be nontoxic to fibroblast and bacterial cells but showed selective toxicity to certain species of filamentous fungi ( Scopulariopsis brevicaulis ) and yeasts ( Cryptococcus neoformans ). The most important aspect of this work is the attempt to explain the mechanisms of action of these compounds by studying their interaction with biological membranes. This was achieved by examining the interactions with model biological membranes representative of given families of microorganisms using Langmuir monolayers. The data obtained partly show correlations between the results for model systems and biological experiments and allow indicating that the selective antifungal activity of cationic β-glucans is related to their interaction with fungal biological membranes and partly lack of such interaction toward cells of other organisms. In addition, the obtained macromolecules were characterized by spectral methods (Fourier transform infrared (FTIR) and 1 H nuclear magnetic resonance (NMR) spectroscopies) to confirm that the desired structure was obtained, and their degree of modification and molecular weights were determined., Competing Interests: The authors declare no competing financial interest., (© 2022 The Authors. Published by American Chemical Society.)

A series of anionic homopolymers, poly(sodium 2-(acrylamido)-2-methyl-1-propanesulfonate) (PAMPS) and amphiphilic copolymers of AMPS and sodium 11-(acrylamido)undecanoate (AaU), both block (PAMPS 75 -b-PAaU n ), and random (P(AMPS m -co-AaU n )), were synthesized and their antiviral activity against Zika virus (ZIKV) was evaluated. Interestingly, while the homopolymers showed limited antiviral activity, the copolymers are very efficient antivirals. This observation was explained considering that under the conditions relevant to the biological experiments (pH 7.4 PBS buffer) the macromolecules of these copolymers exist as negatively charged (zeta potential about -25 mV) nanoparticles (4-12 nm) due to their self-organization. They inhibit the ZIKV replication cycle by binding to the cell surface and thereby blocking virus attachment to host cells. Considering good solubility in aqueous media, low toxicity, and high selectivity index (SI) of the PAMPS-b-PAaU copolymers, they can be considered promising agents against ZIKV infections.

Zika virus (ZIKV) is an emerging mosquito-borne pathogen associated with microcephaly and other congenital abnormalities in newborns as well as neurologic complications in adults. The explosive transmission of the virus in the last ten years put it in the limelight and improved our understanding of its biology and pathology. Currently, no vaccine or drugs are available to prevent or treat ZIKV infections. Knowing the potential of flaviviruses to broaden their geographic distribution, as observed for the West Nile virus, it is of importance to develop novel antiviral strategies. In this work, we identified poly(sodium 4-styrenesulfonate) (PSSNa) as a new polymeric ZIKV inhibitor. We demonstrated that PSSNa inhibits ZIKV replication in vitro both in animal and human cells, while no cytotoxicity is observed. Our mechanistic studies indicated that PSSNa acts mostly through direct binding to ZIKV particle and blocking its attachment to the host cells.

A series of novel aza-BODIPY dyes substituted with p-(dimethylamino)phenyl groups were synthesized and their spectral and electrochemical properties were compared. In particular, the impact of p-(Me 2 N)Ph- groups on these characteristics was of consideration. For two aza-BODIPYs studied, a near-IR absorption band was observed at circa λ abs =796 nm. Due to the pronounced intramolecular charge transfer (ICT) exerted by the presence of strongly electron-donating p-(Me 2 N)Ph- substituents, the compounds studied were weakly emissive with the singlet lifetimes (τ S ) in the picosecond range. Nanosecond laser photolysis experiments of the brominated aza-BODIPYs revealed T 1 →T n absorption spanning from ca. 350 nm to ca. 550 nm with the triplet lifetimes (τ T ) ranged between 6.0 μs and 8.5 μs. The optical properties of the aza-BODIPYs studied were pH-sensitive. Upon protonation of the dimethylamino groups with trifluoroacetic acid in toluene, a stepwise disappearance of the NIR absorption band at λ abs =790 nm was observed with the concomitant appearance of a blue-shifted absorption band at λ abs =652 nm, which was accompanied by a prominent emission band at λ fl =680 nm. The transformation from a non-emissive to an emissive compound is associated with the inhibition of the ICT. As estimated by CV/DPV measurements, all aza-BODIPYs studied exhibited two irreversible oxidation and two quasi-reversible reduction processes. All compounds studied exhibit extremely high photostability and thermal stability., (© 2019 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

In view of the ever-growing demand for efficient triplet photosensitizers and photoactive components of various optoelectronic devices, we herein report the synthesis and properties of hexaiodo-subphthalocyanines (I 6 SubPcs). The improved five-step route to 4,5-diiodophthalonitrile, which serves as precursor for the synthesis of the I 6 SubPcs, is reported. The improved synthesis merely required one chromatographic separation to afford the high-purity target product. Highly desirable photophysical and photochemical properties were induced in the I 6 SubPcs due to the presence of six heavy iodine atoms. In particular, high values of the singlet-oxygen quantum yields (Φ Δ ) ranging from 0.83 to 0.9 were measured. The I 6 SubPcs investigated proved to be phosphorescent at 77 K in 2-MeTHF with emission band maxima (λ P ) located at λ=957 and 970 nm. The excited-triplet-state energies (E T ) were estimated to be approximately 1.30 eV, whereas the triplet lifetimes (τ T ) were found to be 27.7 and 30.1 μs. The CV/DPV measurements indicated that both I 6 SubPcs exhibited one irreversible oxidation and one quasi-reversible reduction. The spectroelectrochemical measurements pointed to a relative stability and reversibility of the electrochemically formed anion radical, that is, I 6 SubPc .- , and an instability of the species formed upon one-electron oxidation, that is, I 6 SubPc .+ . Estimation of E HOMO gave a value of approximately -5.8 eV whereas E LUMO was found to be located at around -3.8 eV., (© 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Perfluorophthalocyanines incorporating three-valent metals, namely In(Cl), Ga(Cl), and Al(Cl), have been synthesized and characterized. Thermogravimetric analysis revealed that these compounds exhibit outstanding thermal stability and a tendency to sublime at a temperature exceeding around 350 °C without thermal decomposition. Cyclic voltammetry (CV) and differential pulse voltammetry (DPV) were used to probe the frontier orbital energy levels of these compounds in THF solution. All three compounds undergo three quasi-reversible reductions with the first one leading to the formation of an anion radical, namely MPc(-.) , as confirmed by spectroelectrochemistry. The compounds studied were intrinsically resistive to oxidation, which indicates that they are very good electron acceptors (n-type materials). The HOMO-LUMO energy gaps (Eg ) of the three compounds determined by UV/Vis spectroscopy were relatively unaffected by the three-valent metals incorporated into the phthalocyanine macrocycle. Similarly, the energies of the HOMO (EHOMO ) and LUMO (ELUMO ) orbitals remained virtually unaffected by the three-valent metals in the perfluorophthalocyanine. Importantly, all the perfluorophthalocyanines studied possess LUMO levels between -4.76 and -4.85 eV, which makes their reduced forms resistant to electron trapping by O2 and H2 O. This property opens up the possibility for the fabrication of electronic devices operating under ambient conditions. All three compounds demonstrated very good photostability as solid thin films., (© 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

New Pd(II) and Pt(II) complexes with a highly electron-deficient ligand (H2 PcF64 ) were conveniently prepared in a three-step synthesis. This is the first time that the phosphorescence of phthalocyanines with a H2 PcF64 framework has been measured. Based on these measurements, the triplet-state energies (ET ) were directly determined. Transient absorption experiments revealed broad T1 →Tn absorption spanning from ca. 350 to ca. 1000 nm and allowed determination of the triplet-state lifetimes. Removal of the Pd or Pt from the perfluoro-phthalocyanine resulted in a significant increase of the triplet lifetime for H2 PcF64 . The very efficient intersystem crossing observed for both PdPcF64 and PtPcF64 leads to residual fluorescence and suppresses the fluorescence lifetimes to less than 50 ps. The absence of Pd and Pt in the perfluoro-phthalocyanine ligand, viz. H2 PcF64 , led to a recovery of fluorescence. Cyclic voltamperometry studies pointed to complete resistance of PdPcF64 and PtPcF64 to oxidation and very strong electron affinity, which rendered these materials very good electron acceptors (n-type materials). The presence of d-orbital metals such as Pd(II) and Pt(II) in the phthalocyanine ring stabilizes their reduced forms, as indicated by the spectroelectrochemical experiments. PdPcF64 and PtPcF64 easily sensitize singlet oxygen production with very high quantum yields. Both phthalocyanines presented resistance to photodegradation in the solid state under aerobic conditions and under intense irradiation., (© 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

The application of Power Doppler mode examination introduced the assessment of vascularisation and measurement of blood flow parameters in lymph node's vessels as a differentiating criterion of benign and malignant lymphadenopathy. However, those criteria appeared insufficient in evaluation of the malignancy grade of enlarged lymph nodes, especially in the cases of lymph nodes with invisible or scantly visible vascularisation in Power Doppler mode. Introducing contrast media in ultrasonographic examinations enabling intensification of the Doppler signal even by 20 dB creates the hope of increasing diagnostic efficacy of ultrasonography in evaluation of vascularisation in lymph nodes enlargement. The purpose of the study was to define the usefulness of ultrasonographic contrast media (Levovist), 3D presentation and harmonic imaging in differential diagnosis of lymph nodes enlargement in children. 32 children with cervical lymph nodes enlargement underwent examination with ultrasonography. In the examinations, Levovist by Schering was used in concentration 300, the amount depending on patient's body mass. The analysis of results obtained in the study revealed that application of contrast media enables better visualisation of lymph node vascularisation. Localisation of the vessels which were not shown in conventional Doppler mode enables visualisation of the vessel architecture in the lymph node and better defining of vascularisation pattern. Application of the new methods of THI and 3D imaging and contrast media in Power Doppler examinations increases the diagnostic efficacy of ultrasonography in differentiating lymph nodes alternations.