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Self-healing materials recover mechanical damages to expand the lifetime of the material provided. In this study, self-healing hydrogels have been successfully prepared using a novel and simple technique. Vanillin is a natural monomer, used as a bio-based cross-linker for UV-induced bonding and Schiff-base bonding. Methacrylate-functionalized vanillin (M-VAN) is covalently integrated with the polymer matrix. While M-VAN supports polymer matrix with its vinyl group, its aldehyde functionality helps the formation of dynamic covalent imine bonds via Schiff-base formation. The hydrogel showed excellent self-healing ability overnight under physiological conditions without external addition. In addition, the hydrogel surface was modified by collagen and its cell viability was investigated. The prepared scaffolds showed good cell viability of 124% and 163% compared to the control sample. The developed self-healing material reveals that it has possible uses for future biomedical applications and tissue engineering studies due to the self-healing mechanism taking place under ambient conditions.

© 2022This work involves the synthesis and characterization of metallic (Co, Fe, Mn, Ni, Zn) ball-type phthalocyanine precursors by using novel 4,4′-(((4-(tert-butyl)-1,2-phenylene)bis-(methylene))bis(oxy))diphthalonitrile starting compound. The classical oxo-bridge in phthalocyanines was altered with the -OCH2- bridge first time for these ball-type phthalocyanine precursors, and the effects of this change on the chemical, physical and spectral features of phthalocyanine complexes were investigated, in the study. The redox properties of phthalocyanines were researched by electrochemical and in situ spectroelectrochemical measurements on a Pt working electrode in non-aqueous medium. The color changes involved in the redox processes were observed via in situ electrocolorimetric techniques. Electrochemical and UV–Vis spectral measurements exhibited that the compounds had reversible and serial one-electron reduction and oxidation processes. Furthermore, they also had nitrile reduction processes because of opened nitrile groups located at peripheral tails of the phthalocyanine complexes. The plentiful redox conducts of the complexes such as Pc ring based and/or central redox active metal-based reduction and oxidation reactions at low potentials showed that these complexes can be used as functional materials. Because of the apparent spectral and net color changes, the complexes are suitable for utilization in electrochromic devices. Moreover, their rich redox features are a sign of their high electrocatalytic activity for oxygen reduction.

© 2022In this study, peripheral and non-peripherally substituted Zn(II) phthalocyanine complexes were synthesized from 7‑hydroxy-3-(p-tolyl)coumarin and 7‑hydroxy-3-(p-tosyl)coumarin compounds. The synthesized new compounds were characterized using elemental analysis, FT-IR, UV–Vis, Fluorescence 1HNMR spectroscopy and MALDI-TOF mass spectrometry. All the synthesized phthalocyanine complexes showed good solubility in organic solvents such as acetone, dichloromethane, chloroform, pyridine, and ethyl acetate. Fluorescent quenching behavior was investigated using 1,4-benzoquinone and potassium iodide as a quencher. The photophysical (fluorescent quantum yields and lifetimes) and photochemical (single oxygen and photodegradation quantum yields) properties of these new phthalocyanines were examined in dimethyl sulfoxide. Phthalocyanine complexes containing 7‑hydroxy-3-(p-tolyl)coumarin had higher singlet oxygen quantum yields than phthalocyanine complexes containing 7‑hydroxy-3-(p-tosyl)coumarin. Phthalocyanines to which coumarins are peripherally bound were more advantageous than their non-peripherally bound derivatives. As a result of their photophysical and photochemical properties, coumarin-phthalocyanine complexes containing tolyl-/tosyl- groups can be used as photosensitizing candidates in photodynamic therapy and can be developed with targeted modifications.

We have synthesized a new zinc(II)-phthalocyanine (ZnPc) incorporating hydroxyl groups at the pe-ripheral positions. This new zinc(II)-tetra-hydroxyphthalocyanine ( 1 ) has been characterized by high -resolution MALDI TOF MS, UV-Vis, FT-IR (ATR), and 1 H-and 13C-NMR techniques, and further by the electrochemical measurements. DFT and TD-DFT computations were performed to model plausible struc-ture and also analyze the electronic structure and optical properties of 1 . The effects of the polarity and hydrogen bonding ability of the hydroxyl substituents on the peripheral positions of 1 on the optical and electrochemical properties are reported in this study. The redox behavior of 1 in dimethyl sulfoxide (DMSO) was determined by voltammetry and colorimetry supported in situ spectroelectrochemistry. The nonlinear absorption and optical limiting (OL) properties of 1 were measured in tetrahydrofuran (THF) by utilizing the open aperture Z-scan technique with nanosecond pulses at 532 nm. The sample demon-strated good reverse saturable absorption and OL behaviors. The ultrafast pump-probe experiments re-vealed the intersystem crossing (ISC) mechanism (triplet-triplet transition) and the nonlinear absorption mechanism of the compound. The results indicate that this new phthalocyanine ( 1 ) can be considered a potential candidate for low-power OL applications.(c) 2022 Elsevier B.V. All rights reserved., Zonguldak Buelent Ecevit University [2015-72118496-05]; Turkish Academy of Sciences (TUBA), The authors thank Zonguldak Buelent Ecevit University for financial support under the project [BAP Project No: 2015-72118496-05 ]. Computer time on TUBITAK-ULAKBIM Truba resources are greatly acknowledged. Ali Riza OEzkaya and Bekir Salih also thank the Turkish Academy of Sciences (TUBA) for partial support to this study.

© 2022New thiosemicarbazides (3, 5-6), 1,2,4-triazoles (14-15) and thioethers (22-68) from derived (S)-Naproxen were synthesized in this study. The structure of these compounds were elucidated by spectral (FT-IR, 1H NMR, 13C NMR) methods, besides elemental analysis and TLC. The molecular binding of the compounds on MetAP-2 was performed. Anticancer effects of the synthesized compounds were studied by using MTT assay method on MCF-7 (includes oestrogene and progesterone receptors) and MDA-MB-231 (lacks estrogen and progesterone receptors) adenocarcinoma cell lines at 0, 10, 25, 50, 75 and 100 μM concentrations for 24 h. The IC50 values of novel (S)-Naproxen derivatives were determined between from 5 to 100 μM on MCF-7 breast cancer cell line and MDA-MB-231 cell lines. The apoptotic activity of selected compounds 22 and 42 were first analyzed by Annexin V staining using Tali Image-Based Cytometer. Mitochondrial membrane potential changes determined in fluorescence plate reader following JC-1 stain for compounds 22 and 42 in MCF-7 and MDA-MB-231 cells. The effect of these compounds on the cell viability 4T1 mouse mammary tumor cell line was tested at 1 to 5 times of calculated IC50 value (IC50x1, IC50x2, IC50x3, IC50x4, and IC50x5). Next in order to determine the toxicity of the combination of compound 51 and Docetaxel, WST-1 cell viability and proliferation assay was performed with 4T1.

© 2022 Elsevier LtdAn experimental cycle-to-cycle analysis in multi-cylinder automotive common-rail compression ignition engine was performed to understand better the combustion in the hydrogen fuelled diesel engine. Hydrogen was fumigated in intake line at a wide-ranging from 0 lpm to 50 lpm in steps of 10 lpm. Test engine was operated at three different loads for a constant engine speed. The relative air–fuel ratios were between 1.55 and 3.31. The combustion occurred with an excess of air in all tests. Combustion data of 120 cycles were used to analyse the cyclic variations, determined by standard deviation of the cylinder pressure. Cyclic variations, coefficient of variance (CoV), standard deviation, frequency, and average value of peak combustion pressure (Pmax), maximum pressure rise rate (PRRmax), indicated mean effective pressure (IMEP), mass fraction burned (MFB), and MFB10-90 duration were analysed. Results showed that for all hydrogen addition levels, CoVs of Pmax, IMEP and MFB10-90 were always found below 3% at all loads, and PRRmax values with hydrogen operations in each cycle were under the limit of knocking combustion. Engine load was the most important factor to affect to CoV, standard deviation, and frequency of the combustion parameters. Minor cyclic variations in MFB traces were found at all engine loads and hydrogen addition levels, which agreed well with the cylinder pressure traces. Frequencies of Pmax and IMEP were moderate in low and medium loads, but reduced in high load, and also the values of Pmax and IMEP in high load were distributed in a wider range compared to low and medium loads. MFB10-90 duration increased for dual-fuel modes, its frequency was decreased, and its distribution was extended with hydrogen addition. Trend of standard deviation was mostly similar to that of CoV for the studied combustion parameters. Furthermore, variations of correlation coefficient (R) among Pmax, PRRmax, IMEP, and MFB10-90 were discussed in this paper, and the highest R value was found between IMEP and Pmax.