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In the present study, the effect of different ratios of GelMA concentration has been exhibited for wound dressing implementation by the electrospinning method using a new polymer combination of Gelatin methacrylate (GelMA)/Polycaprolactone (PCL)/Chitosan (CS). The nanofiber composites were fabricated due to their biocompatible, biodegradable, improved mechanical strength, low degradation rate, and hydrophilic nature to develop cell-mimicking, cell adhesion, proliferation, and differentiation. Different concentrations of GelMA were added to the PCL/CS solution as 5, 10, and 20 wt%, respectively, in the formic acid/acetic acid (7:3) solution. A photoinitiator was added to the solution for photo-crosslinking of GelMA. The influence of different solution concentrations (5, 10, and 20 wt%) on the structure’s nanofiber production and fiber morphology was examined. SEM micrographs revealed that varied GelMA concentrations resulted in suitable and stable nanofiber composites. The average diameter of nanofiber composites grows as the GelMA concentration rises. FTIR, DSC, tensile test, degradation, and swelling test were evaluated. The results demonstrated that high mechanical strength, hydrophilic properties, and a slow degradation rate were observed with the presence and increment of GelMA concentration within the nanofiber composites. The antibacterial potential of GelMA/PCL/CS nanofiber composites was evaluated against P. aeruginosa and S. aureus using a disc diffusion assay. In vitro cell culture research was conducted by seeding NIH 3T3 fibroblast cells on nanofiber composites, proving these cells’ high cell proliferation rate, viability, and adhesion. 10 wt% GelMA-based nanofiber composites were found to have great potential for wound dressing applications.

Cations with suitable sizes to occupy an interstitial site of perovskite crystals have been widely used to inhibit ion migration and promote the performance and stability of perovskite optoelectronics. However, such interstitial doping inevitably leads to lattice microstrain that impairs the long-range ordering and stability of the crystals, causing a sacrificial trade-off. Here, we unravel the evident influence of the valence states of the interstitial cations on their efficacy to suppress the ion migration. Incorporation of a trivalent neodymium cation (Nd3+) effectively mitigates the ion migration in the perovskite lattice with a reduced dosage (0.08%) compared to a widely used monovalent cation dopant (Na+, 0.45%). The photovoltaic performances and operational stability of the prototypical perovskite solar cells are enhanced with a trace amount of Nd3+ doping while minimizing the sacrificial trade-off.

Two different classes of drugs were selected to test the adsorption capacity of carbon nanofibers as a greener new generation alternative adsorbent in simulated gastric and intestinal fluids. Kinetics of the promethazine and trimethoprim adsorption were analyzed using Lagergren first order and Pseudo second order models. Intraparticle diffusion graphs were also plotted to discuss the adsorption mechanism. Kinetic data showed the significance of boundary layer effect for both of the drugs and the presence of intraparticle diffusion as the other rate controlling step for the promethazine adsorption. Giles isotherms showed the high affinity of drug molecules to the adsorbent. Maximum adsorption capacity of drugs was calculated using Langmuir model as 18.35 and 41.15 mg/g for trimethoprim and 95.24 and 80.65 mg/g for promethazine in simulated gastric fluid (SGF) and simulated intestinal fluid (SIF), respectively. Trimethoprim adsorption was under favor of hydrophobic interaction and pi-pi dispersion interactions while promethazine adsorption was through cation exchange where the electrostatic attraction is an important force with the contribution of dispersion interactions.

A new series of 4-methyl-2-{2-[(aryl)methylidene]hydrazinyl}-1,3-thiazole (2a-i), N-(4-acetyl-5-aryl)4,5-dihydro-1,3,4-thiadiazol-2-yl)acetamides (3a-b) and N-(5-(4-(substituted phenyl)-1,3,4-thiadiazol-2-yl)acetamides (3c-i) were synthesized by the reaction of 2-((aryl)methylene)hydrazine-1-carbothioamides (1a-i) and acetic anhydride or chloroacetone. The cytotoxic activities of the products were evaluated by MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay against Hela cervical cancer, MCF-7 breast carcinoma and HT-29 colorectal cancer cell lines. Thiazole based compounds 2a, 2b, 2f and 2i, bearing 4-bromothiophen-2-yl, naphthalen-2-yl, 2,5-difluorophenyl and 4-(trifluoromethoxy)phenyl moieties, respectively; also N-(4-acetyl-5-(naphthalen-2-yl)-4,5-dihydro-1,3,4-thiadiazol-2-yl)acetamide (3b) and N-(5-(2,6-difluorophenyl)-1,3,4-thiadiazol-2-yl)acetamide (3d) exhibited significant anticancer activity against three cancer cell lines. Moreover, these active compounds were further evaluated by apoptotic protein levels. The results showed that these thiazole and thiadiazole compounds induced apoptosis of cancer cells.

Packaging must have a good commercial appearance and is generally obtained by ink transferred to its substrate. It is important that the ink used in packaging printing is produced from environmentally friendly and sustainable raw materials as well as being suitable for the printing system. The increasing demand in the field of printed packaging and the scarcity of resources to meet this demand have accelerated the search for new sources for inks. For this purpose, inks produced in the laboratory using a modified cellulose-based binder, a commercial acrylic resin and a commercial soybean protein were compared with a commercial ink. As a result of the study, it was determined that the printability properties of the ink obtained by using the modified cellulose-based binder were better than the ink obtained with commercial soybean protein. It was determined that it showed printability properties close to the ink produced with commercial acrylic binders. By using modified cellulose-based water-based flexographic ink instead of other commonly used binders, more environmentally friendly sustainable inks can be produced.

In this study, using a new polymer combination of Chitosan(CH)/Xanthan Gum(XG) has been exhibited for wound dressing implementation by the 3D-Printing method, which was fabricated due to its biocompatible, biodegradable, improved mechanical strength, low degradation rate, and hydrophilic nature to develop cell-mimicking, cell adhesion, proliferation, and differentiation. Different concentrations of XG were added to the CH solution as 0.25, 0.50, 0.75, 1, and 2 wt% respectively in the formic acid/distilled water (1.5:8.5) solution and rheologically characterized to evaluate their printability. The results demonstrated that high mechanical strength, hydrophilic properties, and slow degradation rate were observed with the presence and increment of XG concentration within the 3D-Printed patches. Moreover, in vitro cell culture research was conducted by seeding NIH 3T3 fibroblast cells on the patches, proving the cell proliferation rate, viability, and adhesion. Finally, 1% XG and 4% CH containing 3D-Printed patches were great potential for wound dressing applications.

Injecting hydrogen into the natural gas network to reduce CO2 emissions in the EU residential sector is considered a critical element of the zero CO2 emissions target for 2050. Burning natural gas and hydrogen mixtures has potential risks, the main one being the flame flashback phenomenon that could occur in home appliances using premixed laminar burners. In the present study, two-dimensional transient computations of laminar CH4- + air and CH4 + H-2 + air flames are performed with the open-source CFD code OpenFOAM. A finite rate chemistry based solver is used to compute reaction rates and the laminar reacting flow. Starting from a flame stabilized at the rim of a cylindrical tube burner, the inlet bulk velocity of the premixture is gradually reduced to observe flashback. The results of the present work concern the effects of wall temperature and hydrogen addition on the flashback propensity of laminar premixed methane-hydrogen-air flames. Complete sequences of flame dynamics with gradual increases of premixture velocity are investigated. At the flame flashback velocities, strong oscillations at the flame leading edge emerge, causing broken flame symmetry and finally flame flashback. The numerical results reveal that flashback tendency increase with increasing wall temperature and hydrogen addition rate. (C) 2022 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.

Skin is a protective barrier that can protect against environmental influences and renew itself. However, in some cases, this regenerative property is lost, and this causes delays in wound healing. Wound healing is a complex and long-lasting phase. Any bacterial infection during the wound healing process delays wound healing. The therapeutic efficacy can be increased by using nanocarrier drug delivery systems to the target tissue with modern wound dressings. Controlled nano drug delivery systems increase the therapeutic efficacy in the treatment of diseases and provide a faster recovery process. In this study, amoxicillin (AMX) and rifampicin (RIF) were loaded into the bismuth ferrite (BFO) particles which were synthesized with the co-precipitation method. Then, these drug-loaded BFO particles (0.075 %) were added separately to 13 % polyvinyl alcohol (PVA) solution and the solutions were printed three-dimensionally to obtain three dimensional scaffolds. With these designed scaffolds, it is aimed to reduce the risk of inflammation in wound tissues and increase therapeutic efficacy with controlled release. The SEM images proved that homogeneous pore distributions could be achieved with these combinations. The tensile test results showed that drug-loaded BFO addition increased the mechanical strength of the 13 % PVA scaffold. The biocompatibility test results demonstrated that the highest viability values of the human adipose tissue-derived mesenchymal stem cells were obtained for AMX-added 13 % PVA scaffolds.

Bu çalışmada, 2,4-bis-(3-metoksitolil)-1,3-ditiya-2,4-difosfetan 2,4-disülfür ([((CH3)C6H3(OCH3)-P(S)S)2]) bileşiği yeniden sentezlendi. Bu bileşiğin alkollerle reaksiyonundan literatürde bilinen iki ditiyofosfonik asiti ([HS2P(R’)(ORn)], HLn; R’=(CH3)C6H3(OCH3); R1= Etil-, L1, R2= 2-propil-, L2) sentezlendi. Ham ditiyofosfonik asitler kuru amonyak gazıyla ligandlarına ([NH4][S2P(R’)(ORn)]) dönüştürüldü. Etil alkol ortamında bu ligandların kadmiyum tuzlarıyla reaksiyonlarından çift çekirdekli yeni ditiyofosfonato Cd(II) kompleksleri sentezlendi ([Cd(μ-Ln)2(Ln)2]). Komplekslerin yapıları; elementel analizi, kütle spektrometresi (ESI), FT-IR, Raman, NMR (1H, 13C, 31P) spektroskopisiyle aydınlatıldı. In this study, 2,4-bis(3-methoxytolyl)-1,3-dithia-2,4-diphosphetane-2,4-disulfide which is formulated as [((CH3)C6H3(OCH3)-P(S)S)2] compound was resynthesized. From this, two dithiophosphonic acids which were previously known were synthesized from the reaction of this compound with alcohols ([HS2P(R’)(ORn)], HLn; R’=(CH3)C6H3(OCH3); R1= Ethyl-, L1; R2= 2-propyl-, L2). These acids were converted to corresponding ammonium salts, ([NH4][Ln]). The ammonium salts were further reacted with CdCl2.H2O to prepare dinuclear three new dithiophosphonato cadmium(II) complexes, ([Cd(μ-Ln)2(Ln)2]) in ethanol medium. Structures of the complexes were characterized by elemental analysis, mass spectrometry (ESI), FT-IR, Raman, NMR (1H, 13C, 31P) spectroscopy.

Perthiophosphonic acid anhydrides (PTPA) are used as a starting agent in the synthesis of phosphorus-sulfur compounds[1].These derivatives can be classified into dithiophosphates, dithiophosphinates and dithiophosphonates (DTPOA). In this survey, we synthesized new DTPOAs starting from PTPAs formerly synthesized by us ADDIN EN.CITE Bulat202232[32]323217Bulat, ElifSağlam, Ertuğrul GaziZeyrek, Celal TuğrulAkkoç, SenemZorlu, YunusDal, HakanNi(II) complexes with 1,3,2,4-dithiadiphosphetane 2,4-disulfide-based ligands: Structural insights, theoretical studies, and anticancer activitiesApplied Organometallic ChemistryApplied Organometallic Chemistrye6821361020220268-2605https://onlinelibrary.wiley.com/doi/abs/10.1002/aoc.6821https://doi.org/10.1002/aoc.6821[2,3]. In other words, new dithiophosphonic acids (HS2P((2,4-CH3O)2-C6H3)(ORn), HLx,y; RX1=n-propyl-, RX2=2-butyl-,Ry=methyl- were synthesized by reacting of 2,4-bis(3,4-dimethoxyphenyl)-1,3-dithia-2,4-diphosphetane 2,4-disulfide, (SAV-A1) and 2,4-bis(2,4-dimethoxyphenyl)-1,3-dithia-2,4-diphosphetane 2,4-disulfide, (SAV-A2) with aliphatic alcohols. All DTPOAs were transformed to relating to ammonium salts, [NH4Lx,y] (Scheme 1).

Less energy consumption and more efficient use of renewables are among the sustainable energy targets of modern societies. The essential activities to be achieved under these objectives are to increase distributed generation (DG) structures’ applicability. DG systems are small-scale versions of the traditional power grid; they are supported by micro turbines, photovoltaics (PV) modules, hydrogen fuel cells, wind turbines, combined heat and power systems, and energy storage units. The aim of this research is to detail the performance analysis of a proton-exchange membrane fuel cell (PEMFC)-based grid-connected distributed generation system with the help of empirical calculations. To this end, we aimed to establish the system and analyze the performance of the reliable operation of the system with experimental verifications. The findings demonstrate how much power can be generated annually, through real meteorological data, to dispatch to constantly variable loads. While 53.56% of the total energy demand is met by the utility grid, 46.44% of the demand is met by the produced energy i.e., from the DG. The PEMFC-based DG system analyzed in detail in this study was located at Marmara University. According to the results of the performance analysis, significant points of this study will be highlighted to assist the researchers working in this field. Our results are encouraging and can be certified by a larger sample size with neat weather conditions in terms of the percentage of procurement of energy.

This study was carried out in the central district of Kirklareli province in Turkey. It presents the chemical composition of three deposition types, namely wet, bulk and dry. In this study, 150 deposition samples (wet + bulk + dry) were collected for a year in the urban and suburban areas in the central district of Kirklareli. The concentrations of the main cations (Ca2+, K+, Na+, Mg2+, NH4 +) and main anions (SO4 2-, Cl-, NO3 -) in the collected deposition samples were determined. The seasonal variations of the concentrations of the major ions in the three deposition types were studied. The wet and dry deposition fluxes of major ions were calculated. Among the major ions, the ion with the highest annual mean flux values in the wet deposition is Ca2+ in the urban area, while it is Cl- in the suburban area. In the wet deposition, the annual mean flux values of Ca2+ in the urban area and Cl- in the suburban area were 65.40 and 38.09 mg m-2 h-1, respectively. The relationship between ion concentrations and acid deposition was also investigated and the sources of ions were determined. The arithmetic mean pH values of the samples in the urban and suburban areas were 6.39 and 6.14 in wet deposition, 6.75 and 6.41 in bulk deposition, and 7.36 and 6.56 in dry deposition, respectively. The backward trajectories arriving at the region during the study period were divided into two groups. In the first cyclone group, SO4 2- was to 97 % of anthropogenic origin in both the urban and suburban areas.

Günümüzde kansere ve diğer mikroorganizmalara karşı kullanılan ilaçların pek çoğunun biyoyararlanımının düşük olması ve başta toksisite gibi yan etkilerinden dolayı tedavide yeni ilaçların varlığına ihtiyaç duyulmaktadır. Her gün artan sayıda anti-kanser veya antibiyotik ilaç geliştirilmesine rağmen, bu ilaçların seçiciliklerinin düşük olması ve çoklu ilaç direncinin kazanılması, başarılı bir tedavinin önüne geçmektedir. Bu nedenle, tümör hücrelerini veya mikroorganizmaları yok etmek veya en azından çoğalmasını durdurmak için yeni, güçlü ve seçici ajanlarının keşfine önemli ölçüde ihtiyaç duyulmaktadır. Bu çalışma kapsamında 18 adet yeni 1,2,3-triazol/arilidenhidrazid yapısında hibrit bileşik sentezlendi. Elde edilen 18 yeni bileşiğin (17a-r) Staphylococcus Aureus ve Escheric1hia coli bakteri türleri ve Candida albicans mantar türü üzerindeki anti-mikrobiyal etkinlikleri araştırıldı. Elde edilen sonuçlar anti-mikrobiyal ilaç seftazidim ile karşılaştırıldı. Bileşiklerin anti fungal etkinliklerinin MİK değerleri 62.5 μM olarak bulunurken anti-bakteriyel etkinliklerinin MİK değerleri 62.5-125 μM olarak belirlendi.

In this study, a total of 13 compounds (5-17) were synthesized starting from oleanolic acid (OA), a natural triterpenoid. Five new compounds (10, 11, 12, 15 and 17), are the main targets of the study, which were synthesized for the first time in this work as oxime, imine and hydrazone derivatives of OA. Other compounds were previously obtained as natural or semi-synthetically. NMR and HRMS analyses were carried out to determine of structures of all the synthesized molecules. The inhibitory effects of the synthesized compounds on acetylcholinesterase (AChE), human carbonic anhydrase I (hCA I) and II (hCA II) were evaluated. Compounds 13 and 15 showed better inhibitory activity than the other compounds against both hCA I and hCA II isoenzymes, which are competing with AZA. In addition, compound 15 showed the strongest AChE inhibitory activity among all the tested compounds, with an IC50 value of 34.46 mu M.

In this study, with the help of reactive monomers, crosslinkers, and photoinitiator that detect H2S in various matrices, an H2S sensitive fluorescence sensor polymerizes under ultraviolet (UV) light was developed. To this goal, a polymeric membrane was prepared, and the characterization of the membrane was carried out with Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM) methods. Afterward, appropriate conditions were identified, the excitation wavelength was determined as 370 nm, and the emission wavelength was determined as 425 nm. It was established that the fluorescence intensity of the prepared polymeric membrane decreased in the presence of H2S. A detailed analysis was executed to determine the sensor's most suitable pH value and time. It was found that the optimum pH was 8.0, and the optimal duration was 15 s. It has been calculated that the linear range of the developed method is 2.19× 10–8– 6.25× 10–7 M, and the detection limit (LOD) is 7.37× 10–9 M. The effect of some possible interfering ions was investigated, and it determined that the sensor had excellent selectivity. In addition, the sensor used to determine H2S can be used at least 100 times. The recovery percentages were 102.1%–103.2%, and 104.6%, using tap water samples. In terms of providing reliable, fast results, high sensitivity, reusable, low cost, and ease of use, the developed fluorimetric sensor, compared to standard methods, has become more advantageous.

The quest for sustainable monomers and \"green\" synthetic pathways for the design, fabrication, and modification of various polymers is of great importance and attracts a great deal of attention. Here, a highly versatile and novel bio-based platform was developed by reacting castor oil with propiolic acid for performing amino-yne click reactions. Owing to the electron-deficient nature of the propiolic acid esters, amino-yne click reactions were conducted with ease at room temperature, in the absence of any catalyst and solvent (as long as the amines were low-viscosity liquids at room temperature), and within 5 min. Several primary and secondary amines were shown to react readily with the developed platform. Furthermore, thermosets were prepared by using the propiolated castor oil and multifunctional amines. The prepared thermosets displayed improved thermal properties and elastomer-like mechanical properties.

Natural dyes have grown in popularity due to their eco-friendliness. They can be used as a substitute for synthetic dyes to minimize environmental pollution. This research investigates the natural colouring behaviour of haar singhar flower (HSF) extract in cotton dyeing. Colorant was extracted under various conditions utilizing various extraction mediums such as aqueous, basic, and acidic. On cotton, it was discovered that applying 55 mL of aqueous extract containing 1.5 g/100 mL sodium chloride for 40 minutes at 70 °C yielded the best colour output. A new hue with good colour fastness was developed utilizing chemical and bio-mordants. The existence of nyctanthin as a colouring agent in haar singhar flowers was discovered through FTIR analysis of the extract. The CIE Lab system revealed that using 2 g/100 mL of pistachio shell as a bio-mordant resulted in good quality reddish yellow hues. It was discovered that ultrasonic radiations have a high potential for isolating colourants and dyeing cotton fabric under decreased conditions of temperature, time and volume. The application of biomordants has made the procedure greener, more efficient, and safer.

A fast procedure obtained by the combination of fabric phase extraction (FPSE) with high performance liquid chromatography (HPLC) has been developed and validated for the quantification of favipiravir (FVP) in human plasma and breast milk. A sol-gel polycaprolactone-block-polydimethylsiloxane-block-polycaprolactone (sol-gel PCAP-PDMS-PCAP) coated on 100% cellose cotton fabric was selected as the most efficient membrane for FPSE in human plasma and breast milk samples. HPLC-UV analysis were performed using a RP C18 column under isocratic conditions. Under these optimezed settings, the overall chromatographic analysis time was limited to only 5 min without encountering any observable matrix interferences. Following the method validation pro-cedure, the herein assay shows a linear calibration curve over the range of 0.2-50 mu g/mL and 0.5-25 mu g/mL for plasma and breast milk, respectively. The method sensitivities in terms of limit of detection (LOD) and limit of quantification (LOQ), validated in both the matrices, have been found to be 0.06 and 0.2 mu g/mL for plasma and 0.15 and 0.5 mu g/mL for milk, respectively. Intraday and interday precision and trueness, accordingly to the International Guidelines, were validated and were below 3.61% for both the matrices. The herein method was further tested on real samples in order to highlight the applicability and the advantage for therapeutic drug monitoring (TDM) applications. To the best of our knowledge, this is the first validated FPSE-HPLC-UV method in human plasma and breast milk for TDM purposes applied on real samples. The validated method provides fast, simple, cost reduced, and sensitive assay for the direct quantification of favipiravir in real biological matrices, also appliyng a well-known rugged and cheap instrument configuration.

Type 2 diabetes mellitus (T2DM) is a chronic disease characterized by impaired insulin secretion, sensitivity, and hyperglycemia. Diabetic wounds are one of the significant complications of T2DM owing to its difficulty in normal healing, resulting in chronic wounds. In the present work, PCL/PVA, PCL/PVA/PCL, and metformin-loaded, PCL/PVA-Met and PCL/PVA-Met/PCL hybrid scaffolds with different designs were fabricated using 3D printing. The porosity and morphological analysis of 3D-printed scaffolds were performed using scanning electron microscopy (SEM). The scaffolds’ average pore sizes were between 63.6 ± 4.0 and 112.9 ± 3.0 μm. Molecular and chemical interactions between polymers and the drug were investigated with Fourier transform infrared spectroscopy (FT-IR) and X-ray diffraction (XRD). Mechanical, thermal, and degradation analysis of the scaffolds were undertaken to investigate the physico-chemical characteristics of the scaffolds. Owing to the structure, PCL/PVA/PCL sandwich scaffolds had lower degradation rates than the bi-layer scaffolds. The drug release of the metformin-loaded scaffolds was evaluated with UV spectrometry, and the biocompatibility of the scaffolds on fibroblast cells was determined by cell culture analysis. The drug release in the PCL/PVA-Met scaffold was sustained till six days, whereas in the PCL/PVA-Met/PCL, it continued for 31 days. In the study of drug release kinetics, PCL/PVA-Met and PCL/PVA-Met/PCL scaffolds showed the highest correlation coefficients (R2) values for the first-order release model at 0.8735 and 0.889, respectively. Since the layered structures in the literature are mainly obtained with the electrospun fiber structures, these biocompatible sandwich scaffolds, produced for the first time with 3D-printing technology, may offer an alternative to existing drug delivery systems and may be a promising candidate for enhancing diabetic wound healing.

Abstract: Some novel triazole-bearing ketone and oxime derivatives were synthesized from Ibuprofen. In vitro cytotoxic activities of all synthesized molecules against five cancer lines (human breast cancer MCF-7, human lung cancer A549, human prostate cancer PC-3, human cervix cancer HeLa, and human chronic myelogenous leukemia K562 cell lines) were evaluated by MTT assay. In addition, mouse embryonic fibroblast cells (NIH/3T3) were also evaluated to determine the selectivity. Compounds 18, 36, and 45 were found to be the most cytotoxic, and their IC50 values were in the range of 17.46–68.76 µM, against the tested cancer cells. According to the results, compounds 7 and 13 demonstrated good anti-inflammatory activity against the microsomal enzyme prostaglandin E2 synthase-1 (mPGES-1) enzyme at IC50 values of 13.6 and 4.95 µM. The low cytotoxicity and non-mutagenity of these compounds were found interesting. Also, these compounds significantly prevented tube formation in angiogenesis studies. In conclusion, the anti-inflammatory and angiogenesis inhibitory activities of these compounds without toxicity suggested that they may be promising agents in anti-inflammatory treatment and they may be supportive agents for the cancer treatment. Graphical abstract: [Figure not available: see fulltext.].

This work aimed to comprehensively assess the influence of various surface modifications on the formation of apatite ability for EBM Ti-6Al-4V alloy. Sandblasting (S), acid-etching (E), sandblasting and acid-etching (SE), anodization (NA), micro-arc oxidations in 1M H2SO4solution (SM) and 1M H3PO4solution (PM) methods were applied to modify electron beam melted (EBM) Ti-6Al-4V surface. The α/α’-Ti structures and TiO2phases were detected by XRD. The surface roughness (Ra) values ranged from 0.25 μm and 2.86 μm. The wettability of samples was between around 25° and 104°. The SM sample possessed the lowest contact angle. In vitro tests were employed in the simulated body fluid (SBF) solution for 28 days. The samples with different surface textures demonstrated bioactive behaviors. In vitro test results showed that apatite layers formed on the surfaces. The SM sample exhibited good apatite formation ability when the Ca/P ratios were considered. The apatite formation for the SM sample might derive from high roughness, low contact angle value, the existence of Ti-OH groups, and anatase and rutile phases. The SM can be implemented to boost bioactivity on EBM Ti-6Al-4V alloys.

A series of 3-aryl coumarin derivatives and 3-phenylazo-4-hydroxycoumarin were evaluated for their monoamine oxidase (MAO) A and B inhibitory activity and selectivity by fluorometric enzymological assays. Among 21 coumarin derivatives, compound 21 (3-phenylazo-4-hydroxycoumarin) displayed a good inhibitory activity (0.12 +/- 0.02 mu M) and very high selectivity for MAO-B (SI > 833.33). The inhibition was determined as mixed-type and not time-dependent. Docking studies, molecular dynamics and molecular mechanics/Poisson-Boltzmann surface area (MM/PBSA) calculations were performed to elucidate in vitro results. Our results reveal that the insertion of an azo linker between coumarin and phenyl rings in 3-arylcoumarins enhances MAO-B selectivity enormously since such a linker leads to the perfect alignment of the coumarin ring in the aromatic cage and the phenyl ring in the entrance cavity of MAO-B active site. Hydrogen bond interactions with Cys172 in the active site entrance of MAO-B also contributes to the remarkably higher inhibitory activity and selectivity for MAO-B.

In this study, we examined the effects of different doses (100, 500, 1000, 3000, and 5000 ppm) of zinc oxide nanoparticles (ZnO NPs) on the total hemocyte count and hemocyte-mediated immune responses of the Greater Wax Moth Galleria mellonella (Lepidoptera: Pyralidae). The results showed that NPs caused a decrease in hemocyte count at 1000, 3000, and 5000 ppm doses. To investigate the effects of ZnO NPs on the encapsulation and melanization response of G. mellonella, the pre-dyed Sephadex chromatography beads were injected into the hemolymph of each last-instar larva. Larvae were dissected in the 4th and 24th hours after the injection. The level of the encapsulation response and melanization status around the beads were determined under microscopy. The analyses of the beads injected into the insects as encapsulation targets revealed that the number of weakly encapsulated beads increased significantly at 100, 1000, 3000, and 5000 ppm doses when compared to the control group after a short (4-h) post-injection. The number of melanized beads increased significantly at 100, 1000, and 3000 ppm doses in comparison to the control group after the short (4-h) post-injec- tion. Finally, the number of melanized beads decreased significantly at 1000 and 5000 ppm doses when compared to the control group after the long-term (24-h) post-injection. Marmara University Scientific Research Project Coordination Unit (BAPKO), Project No. FEN-C-DRP-100713-0334.

In this study, two novel silicon phthalocyanines (SiPc) having axial anchoring groups (3: SiPc carrying bis-dibutyl phenoxy acrylic acid and 5: SiPc carrying bis-dibutyl phenoxy carboxylic acid) are synthesized as the photosensitizers of dye sensitized solar cells (DSSCs). The obtained novel photosensitizers are elucidated by using 1H NMR, MALDI-TOF, FT-IR, UV-Vis spectroscopy, and elemental analysis. Moreover, the electrochemistry of SiPcs is investigated with voltametric and in-situ spectroelectrochemical analysis. Both SiPcs illustrate similar two reductions and one oxidation Pc based redox processes. In-situ spectroelectrochemical results support the Pc based characters of the voltametric responses. The chromaticity diagrams and optical responses of the anionic and cationic moieties are recorded with the in-situ spectroelectrochemistry to determine the viability of them for various photoelectrochemical usage. Finally, SiPcs are investigated as dyes in DSSCs in order to investigate the influence of bis-dibutyl phenoxy acrylic acid and bis-dibutyl phenoxy carboxylic acid anchoring groups to the photovoltaic performance of SiPcs. DSSCs sensitized with SiPc (3) and SiPc (5) illustrate good photovoltaic performance with 1.48 and 1.99 mA/cm2 short circuit current density, 0.751 and 0.657 V open circuit potential, 0.52 and 0.57 fill factor, and 0.57% and 0.75% power conversion efficiency respectively.

International audience; Nanofluids have emerged as powerful instruments in heat transfer applications due to their improved thermophysical properties. Additionally, many heat transfer equipments are started to be operated within the range of transitional flow regions in the advances in thermal management enhancement techniques. However, up to date, the friction factor and heat transfer coefficient features of nanofluids within the transitional flow regions and the effect of nanoparticle addition into the base fluid on the laminar-to-turbulent transition characteristics are still not understood clearly with contradictory published results. At this point, this paper comprehensively reviews the studies dealing with the nanofluid flow within the transitional flow regions for internal flow applications. After the presentation of applications of nanofluid flow in the transitional flow regions, the nanofluid properties such as nanoparticle type and concentration and base fluid type in the reviewed studies are given in detail. The pressure drop and heat transfer features of nanofluid flow within the transitional flow regions are distinctly identified and discussed for internal flows. The effect of the nanoparticle addition into the liquid on the transition onset is discussed with results from different research groups. A complete evaluation, challenges and further studies are proposed based on available results in the literature.

Serum albümin, kan plazmasında en yaygın bulunan proteinlerden biridir. Ozmotik basıncın ayarlanması,kan pH’nın belirlenmesi ve serbest radikallerin azaltılması gibi birçok farklı fizyolojik görevlerinin yanı sırakanda bulunan endojen ve eksojen maddelerin (yağ asitleri, ilaçlar ve metabolitler vb.) taşınmasında birincilişlevi olan çok fonksiyonlu ve önemli bir proteindir. İlaçlar hedeflerine ulaşmak için kan plazmasındataşınırken kaçınılmaz olarak serum albümin ile etkileşime girmektedirler. Serum albümin ile ilaç etkileşimiilacın terapötik etkisi hakkında bilgi vermektedir. Bu etkileşimlerin incelenmesi ilaç kimyasında, tıpta,biyoteknolojide ve biyokimyada önemli bir araştırma alanıdır. Sığır serum albümin (BSA), 582 amino asitkalıntısından oluşan ve insan serum albümini ile %76 benzerliği olan bir proteindir. Düşük maliyetli olması,yaygın olarak bulunabilmesi ve saflaştırma işleminin kolay olması nedeniyle BSA, araştırmacılar tarafındanligandların proteine bağlanma çalışmaları için sıklıkla tercih edilen, protein-ilaç etkileşimleri ve bağlanmamekanizmalarının belirlenmesi için model olan bir taşıma sistemidir. Kumarinler bir benzen halkası ilebir α-piron halkasının kaynaşması sonucu oluşan benzopiron adı verilen bir bileşik sınıfının üyesidirler.Doğal olarak bitkilerde bulunabildiği gibi sentetik olarak da elde edilebilmektedir. Kumarinlerin sahipoldukları konjuge çift halka sistemleri, onları farklı araştırma alanları için ilginç moleküller haline getirmiştir.Kumarin türevleri geniş bir biyolojik aktivite yelpazesi sergilemektedirler. Bunlar arasında anti-oksidan,anti-enflamatuar, anti-bakteriyel, anti-viral, anti-tümör ve anti-koagülan özellikleri öne çıkmaktadır.Kumarinler tıpta ve özellikle ilaç endüstrisinde yaygın olarak kullanılmaktadırlar. Çalışmamızda uygunEmilim, Dağılım, Metabolizma ve Atılım (ADME) özelliklerine göre farmakokinetik ve farmakodinamiketkileri iyi olan daha önceden sentezlenmiş ve karakterize edilmiş kumarin türevlerinin BSA’ya bağlanmalarıve taşınmaları in silico ve in vitro yöntemlerle araştırılmıştır. In silico çalışmalarda moleküler yerleştirme(moleküler docking) ve in vitro çalışmalarda UV-vis absorbans, floresans gibi multi-spektroskopik yöntemlerkullanılmıştır. BSA ile kumarin türevlerinin etkileşimleri in silico ve in vitro yöntemlerle aydınlatılmıştır. Insilico çalışmalar sonucunda kumarinlerin bağlanma enerjileri, ligand verimliliği değerleriyle birlikte proteinligandetkileşimleri ve konformasyonları belirlenmiştir. Ayrıca in vitro multi-spektroskopik analizlerindeğerlendirilmesiyle; bileşikler BSA’nın floresans şiddetinde, absorbansında ve ikincil yapısında değişikliklerizlenmiş, kuençleşme mekanizmaları, bağlanma sabitleri ve bağlanma bölgelerinin sayıları belirlenmiştir.

Nitrik oksit (NO), gaz halinde bulunan bir sinyal molekülüdür. Nitrik oksit sentazlar (NOS) ise, arjininden nitrik oksit sentezleyen enzimlerdir. Nitrik oksit sentazın (NOS) insanda 3 izoformu bulunmaktadır. Bunlardan nöronal nitrik oksit sentaz (nNOS) ve endotelyal nitrik oksit sentaz (eNOS) NO üretimi üzerinde etkili iken, indüklenebilir nitrik oksit sentaz (iNOS) ise patojenlere karşı bağışıklık işlemlerinde etkili olurlar.Bu üç enzimde birbirine çok yakın bir yapıya sahiptir. Bu yüzden seçimli inhibitörlerin belirlenebilmesi için farklı ligandlar kullanılarak enzimlerin aktif bölgelerindeki farkları incelemek gerekmektedir. Nöronal nitrik oksit sentazın seçimli inhibisyonu, sinir sistemi üzerinde etkili olan Parkinson ve Alzheimer gibi hastalıklara karşı umut verici tedavi yaklaşımı olarak ortaya çıkmaktadır.Kumarinler, 1,2-benzopiron (C9H6O2) olarak karakterize edilen ve yaygın olarak bitkilerde bulunan doğal ürünlerdir. Ayrıca, bitkiler dışında sentetik olarak üretilmekte olup, bazı bakteri ve mantar türlerinde bulunurlar. Kumarinler, geniş bir yelpazede farklı farmakolojik özellikler göstermektedir. Literatürde kumarin türevlerinin; anti-koagülanlar, anti-HIV ajanları, anti-oksidanlar, anti-tümörler ve serbest radikal temizleyicileri olarak farmakolojik olarak yararlı olduğu ve endüstriyel alanlarda geniş uygulamalara sahip olduğu bilinmektedir. Bu çalışmamızda çeşitli kumarin bileşiklerin nitrik oksit sentaz izoenzimleri üzerindeki etkilerinin moleküler doking yoluyla in siliko olarak incelenmiştir. Ayrıca bu çalışmada kullanılan kumarin bileşiklerinin Emilim, Dağılım, Metabolizma ve Atılım (ADME) özellikleri ve Lipinski 5 kuralına uygunluğu da araştırılmıştır. Bu duruma uygun olan kumarin bileşikleri protein veri bankasından indirilen enzimlerle moleküler doking çalışmaları gerçekleştirilmiş ve bu enzimlere bağlanma durumları incelenmiştir. Moleküler doking sonucunda nNOS enzimine bağlanma afinitesi güçlü olan kumarin türevleri ileride Parkinson ve Alzheimer gibi sinir sistemini etkileyen hastalıklara karşı yeni ilaçların geliştirilmesinde katkıda bulunabileceği düşünülmektedir.

New 2,4- bis (2,4-dimethoxyphenyl)-1,3-dithia-2,4-diphosphetane 2,4-disulfide, (SAV-A2), was synthesized from the reaction P 4 S 10 and 1,3-dimethoxybenzene. SAV-A2 was reacted with alcohols to form dithiophos- phonic acid monoesters (HLn, HS 2 P((2,4-CH 3 O) 2 C 6 H 3 )(ORn); n = 1–3, R1 = 2–butyl–; R2 = n -pentyl-; R3 = 4–tert –but-benzyl-). The acids were converted to the ammonium salts ([NH 4 L n ]) to serve as the source of the ligands (Ln), to obtain Ni(II) complexes, ([N i (L n ) 2 ]). [Ni(L2) 2 ] crystal structure was elucidated by single-crystal X-ray diffraction analysis. In addition, Density Functional Theory (DFT) calculations of [Ni(L2) 2 ] was performed. The molecular docking studies of the complex with liver cancer protein, PDB ID: 3WZE and colon cancer antigen proteins, ID 2HQ6 were done compare with experimental and the- oretical results. All compounds were tested on liver- and colon cancer cell lines. Among the complexes tested, [Ni(L3) 2 ] showed an activity closer to that of cisplatin against the colon cancer cell line. The other compounds were found to be have less active.

The first synthesis of 2,4-bis(3,4-dimethoxyphenyl)-1,3-dithia-2,4-diphosphetane 2,4-disulfide (SAV-A1 reagent) was achieved. Seven oxo-alkyl esters (HLn) were synthesized thereof. Ni(II) complexes ([Ni(Ln)(2)]) of these ligands were prepared in ethanol. The structures were identified by spectral studies. Ni(II) complexes were unambiguously determined by X-ray crystallography. In addition, the ligands and their Ni(II) complexes were tested on two different human cancer cell lines, including liver and colon. Moreover, density functional theory (DFT) calculations of the Ni(II) complexes were performed, and the molecular docking studies of these compounds with liver cancer protein, PDB ID: 3WZE and colon cancer antigen proteins, ID 2HQ6 were presented to investigate and predict potential interactions.

Önemli bir eser element olan nikel, başta metal sanayiisi olmak üzere kozmetik, mobilya, aydınlatma gibi sektörlerde de bol miktarda kullanılmaktadır. Canlı metabolizmasında fazla bir biyolojik görevi olmasa da vücuda girdiğinde zehirleyici, toksik, alerjik ve kanserojen etkisi bulunmaktadır. Bu yüzden Nikelin vücutta diğer eser elementlerde de olduğu gibi dengede tutulması gerekmektedir. Vücuttaki fazla Nikel miktarı veya içeriği, solunum yetmezliği ve bronşit, alerjik reaksiyonlar, kalp rahatsızlıkları, doğum kusurları ve kanser gibi birçok hastalığa neden olabilmektedir (1). Bu nedenle de çevresel sistemler (toprak, hava ve su) ve insanlarda bu elementin değerlerinin tespit edilerek takip edilmesi son derece önemlidir. Ni(II) iyonu tayini için yapılan pek çok çalışma bulunmaktadır. Ancak bu yöntemler geniş sonuç aralığı ve iyi tespit limitlerine sahip olsalar da deney prosedürünün uzun sürüyor olması, pahalı cihaz ve kimyasal ekipmanların gerekliliği ve numune hazırlama sürecinde oluşabilecek potansiyel hatalar bu yöntemlerin dezavantajlarındandır(2-5). Çalışmamızda Ni(II) iyonu tayininde kullanılmak üzere polimer esaslı bir membran hazırlanmış ve hazırlanan bu polimerik membran ile hızlı ve yüksek hassasiyette olan çevre dostu yeni bir spektrofluorimetrik yöntem geliştirilmiştir. Polimerik membranın karakterizasyonunu takiben tayin için gerekli olan dalgaboyu, süre, pH vb parametreler ayrıntılı bir şekilde incelenmiştir. Ardından seçicilik ve gerçek örneklere uygulanabilirliği araştırılmıştır. Bu amaçla sertifikalı standart referans atık su numuneleri kullanılmıştır. Geliştirilen yöntem kullanılarak Ni(II) iyonu seçici bir şekilde ve yüksek bir hassasiyetle tayin edilebilmektedir. Teşekkürler: “Bu çalışma Marmara Üniversitesi Bilimsel Araştırma Projeleri Koordinasyon Birimi tarafından FYL-2022-10390 nolu proje kapsamında desteklenmiştir.” Anahtar Kelimeler: Nikel(II), Fluoresans, Polimerik Sensör

The energetic viability of the previously proposed biogenetic pathway for the formation of two unique monoterpenoid indole alkaloids, voacafricine A and B, which are present in the fruits of Voacanga africana, was investigated using density functional theory computations. The results of these calculations indicate that not only is the previously suggested pathway not energetically viable but also that an alternative biosynthetic precursor is likely.

Researchers are focusing their efforts on renewable energy sources to avoid future global energy and environmental crises. One of the renewable energy sources, biomass, can be processed using a variety of techniques and thermodynamic cycles. Biomass gasification, for example, has several environmental and technical benefits. Biochar, on the other hand, is produced by the use of a thermal pretreatment technique to biomass, and it can be used to overcome the drawbacks of biomass in gasification operations. Despite the fact that biochar improves the quality and volume of syngas, there is a few research on this topic in the literature. Although researchers have used a variety of process simulators, the number of gasification systems developed in the Aspen HYSYS simulator is very limited, and no circulating fluidized bed (CFB) gasification model for biochar gasification has ever been reported to our knowledge. Based on the non-stoichiometric equilibrium technique, a unique CFB gasifier model was developed in this work. The impacts of various operating parameters on the syngas were evaluated. In addition, the gasification performance of 10 biochar samples with varying physicochemical features was compared to the physicochemical qualities of solid fuels in a steam and CO2 mixture. As a result, biochar samples with a high carbon content formed an H2-rich syngas with a high calorific value during steam gasification. According to parametric studies, the optimum gasification temperature is about 700 ◦C, the optimum gasification pressure is 1 bar, and the optimum ratios of steam/biochar and CO2/biochar are between 0.2–0.3 and 0.5–1.0, respectively.

The novel and highly soluble cobalt(II), copper(II) and manganese(III) phthalocyanines ((Pc-Co, Pc-Cu, and Pc-Mn) bearing 3-(5-(3,5-dimethoxyphenyl)-1-phenyl-4,5-dihydro-1H-pyrazol-3-yl)phenol have been synthesized and characterized by FT-IR, NMR, UV-Vis and mass spectroscopic methods. Additionally, electrochemical and spectroelectrochemical properties of these phthalocyanine compounds were investigated. Due to the redox inactivity of the Cu2+ central cation of (Pc-Cu), Pc based reductions and oxidation processes are recorded. [(CoPc2-)-Pc-II]/[(CoPc2-)-Pc-I](1-) and [(CoPc2-)-Pc-II]/[(CoPc2-)-Pc-III](1+) couples for the central metal redox reactions, and [(CoPc2-)-Pc-I](1-)/[(CoPc3-)-Pc-I](2-), [(CoPc3-)-Pc-I](2-)/[(CoPc4-)-Pc-I](3-) and [(CoPc2-)-Pc-III](1+)/[(CoPc1-)-Pc-III](2+) couples for the Pc based reduction and oxidation are observed respectively with (Pc-Co). Like (Pc-Co), (Pc-Mn) also illustrated metal-based reduction processes, [Cl1--(MnPc2-)-Pc-III]/[Cl1--(MnPc2-)-Pc-II](1-) and [Cl1--(MnPc2-)-Pc-II](1-)/[Cl1--(MnPc2-)-Pc-I](2-) in addition to the Pc based [Cl1--(MnPc2-)-Pc-I](2-)/[Cl1--(MnPc3-)-Pc-I](3-), [Cl1--(MnPc3-)-Pc-I](3-) /[Cl1--(MnPc4-)-Pc-I](4-) and [Cl1--(MnPc2-)-Pc-III]/[Cl1--(MnPc1-)-Pc-III](1+) redox couples were also recorded. These redox mechanisms were supported with the characteristic spectral changes observed during the in-situ spectroelectrochemical measurements. Especially metal-based electron transfer changes caused distinct spectral and color changes, which are the desired properties of the complexes for the possible opto-electrochemical applications. (C) 2022 Elsevier B.V. All rights reserved.

Amino acid conjugates are described by the reaction of amino acids with bioactive organic groups such as vitamins, hormones, flavonoids, steroids, and sugars. In this study, 12 new conjugates were synthesized by reaction of cinnamic acid derivatives with various amino acids. Cytotoxic studies against four different human cancer cells (MCF7, PC-3, Caco-2, and A2780) were carried out by MTT assay method at five different concentrations. The structure-activity relationships based on the cell viability rates were evaluated. To compare the anticancer activities of the compounds using computational chemistry methods, they were docked against A2780 human ovarian cancer, Michigan Cancer Foundation-7 (MCF7), human prostate cancer (PC-3) and human colon epidermal adenocarcinoma (Caco-2) cell lines and compared with the standard 5-Fluorouracil. The results indicate that the efficacy of cinnamic acid derivatives increases with the presence of amino acids. Comet assay was conducted to understand whether the cell deaths occur through DNA damage mechanism and the results exhibit that the changes in the specified parameters were statistically significant (p

In this study, perthiophosphonic acid anhydrides which are previously synthesized (2,4-bis(3-methoxytolyl)-1,3-dithia-2,4-diphosphetane-2,4-disulfide ([((3-methoxytolyl)P(S)S)2], SAV-B1 reagent and 2,4-bis(ferrocenyl)-1,3,2,4-dithiadiphosphetane-2,4-disulfide [((ferrocenyl)P(S)S)2], FcLR, Ferrocenyl Lawesson's Reagent) react with alcohols to obtain new dithiophosphonic acids (3-methoxytolyl=(CH3)(OCH3)C6H3- and Xn=Alkyl group (R) for SAV-B1, HXn; R1=3-pentyl-, HX1; R2=2-butyl-, HX2; R3=2-pentyl-, HX3 and Fc=Ferrocenyl- and Yn=Alkyl or aryl group (R') for FcLR, HYn; R'1=4-tert-cyclohexyl-, HY1; R'2=2-phenyl-1-propyl-, HY2). These products were later transformed into their ammonium salts ([NH4][Xn], [NH4][Yn]). The structures of ammonium salts were characterized by mass, FT-IR, 1H-, 13C- and 31P-NMR spectroscopy and elemental analysis.

A combined strategy of computational, protein engineering and cross-linked enzyme aggregates (CLEAs) approaches was performed on Bacillus lehensis G1 maltogenic amylase (Mag1) to investigate the preferred amino acids and orientation of the cross-linker in constructing stable and efficient biocatalyst. From the computational analysis, Mag1 exhibited the highest binding affinity towards chitosan (-7.5 kcal/mol) and favours having interactions with aspartic acid whereas glutaraldehyde was the least favoured (-3.4 kcal/mol) and has preferences for lysine. A total of eight Mag1 variants were constructed with either Asp or Lys substitutions on different secondary structures surface. Mutant Mag1-mDh exhibited the highest recovery activity (82.3%) in comparison to other Mag1 variants. Mutants-CLEAs exhibited higher thermal stability (20-30% activity) at 80 °C whilst Mag1-CLEAs could only retain 9% of activity at the same temperature. Reusability analysis revealed that mutants-CLEAs can be recovered up to 8 cycles whereas Mag1-CLEAs activity could only be retained for up to 6 cycles. Thus, it is evident that amino acids on the enzyme's surface play a crucial role in the construction of highly stable, efficient and recyclable CLEAs. This demonstrates the necessity to determine the preferential amino acid by the cross-linkers in advance to facilitate CLEAs immobilisation for designing efficient biocatalysts.

Hereby, fabrication of hyaluronic acid/gelatin/sodium alginate (HA/Gel/SA) polymeric films, which contain electroconductive poly(3,4ethylenedioxythiophene)/poly(styrenesulfonate) (PEDOT:PSS) particles, is studied for drug release applications. The characterization of synthesized PEDOT:PSS and HA/Gel/SA-(PEDOT:PSS) films is verified by using FT-IR and RAMAN spectroscopy. Conductivity values of the films containing 0, 4, and 6% v/v PEDOT:PSS are found via a four-point probe technique to determine the optimum composition of the films for the targeted field. Additionally, swelling, mechanical, and cytotoxicity tests are carried out according to the related methods. Ciprofloxacin (CIP), which is a commonly used antibiotic, is loaded into the polymeric matrix and its release behavior is investigated. All results indicate that the incorporation of PEDOT:PSS increases the mechanical performance and decreases the burst release of drug resulted in more sustained release profile. The HA/Gel/SA-(PEDOT: PSS) formulation is clearly a promising drug carrier that also supports cell viability due to its high cytocompatibility.

Streptomycin (STR) and dihydrostreptomycin (DSTR) are the typically encountered aminoglycoside (AMG) residues in honey. For AMG analysis, studies in literature involve impractical and expensive applications such as ion-pairing chromatography, immunoassays, pre and post column derivatizations, or SPE approaches. Pre -treatments of these methods are toilsome and costly. Herein, one-pot, aqueous in-situ derivatization method was presented as a superior protocol. Time and cost-efficient UHPLC-MS/MS method has been developed, and practical sample preparation was introduced. Satisfactory results were reported in method verification studies. The mean recovery values were 102.6% for STR and 101.3% for DSTR. Average values between 1.5% and 9.9% RSDs were found at intra and inter-day precisions. CC alpha (5.7 and 5.8 mu g/kg) and CC beta (6.2 and 6.4 mu g/kg) values were calculated for STR and DSTR respectively. AMG residues were found in 29 out of 110 analyzed samples using validated method. Described novelty enabled comprehensive analysis in an inexpensive and straightfor-ward manner.

The use of metal-free click reactions for the design and synthesis of novel flame retardant reactive monomers for thiol-ene photopolymerization is an intriguing area of research. In this study, we have prepared a new, 9,10-dihy-dro-9-oxa-10-phosphaphenanthrene-10-oxide (DOPO)-based, P-and N-containing reactive flame retardant via the metal-free azide-alkyne click reaction. For this purpose, first, azide-functionalized DOPO (DOPO-N-3) has been synthesized via Atherton-Todd reaction, and then this compound has been reacted with acetylene dicar-boxylic acid diallyl ester (ACDAE) to give the flame retardant monomer, namely DOPO-triazole diallyl ester (DTDAE). As prepared flame retardant monomer was characterized by nuclear magnetic resonance (NMR) and Fourier-transform infrared spectroscopy (FTIR) spectroscopies. Thermoset materials prepared by using DTDAE displayed over 90% gel content values. Polar triazole and phosphorous units rendered the surface of the ther-mosets hydrophilic. The thermal stability of the networks was enhanced, char yields increased and the glass transition temperatures (T(g)s) were increased. The limiting oxygen index (LOI) values of the crosslinked materials increased up to 27.8% as the DTDAE content was increased in the formulations. The synthetic method described in this study provides a practical approach for the synthesis of a P-and N-containing flame retardant through a metal-free azide-alkyne click reaction Also, the fact that DTDAE is in a liquid state makes this study valuable as it indicates that it can be easily dispersed. It is also believed this promising compound can be used in different polymer structures and formulations to develop new flame retardants in future studies to be applied in industrial applications.

In this study, cinnamic acid derivatives were synthesized from the reaction of benzaldehyde derivatives with malonic acid in the presence of pyridine and piperidine. These compounds were then respectively reacted with glycine and L-alanine methyl ester hydrochloride based on triazine methodology to obtain novel cinnamoyl-amino acid ester derivatives. The structure of these compounds were established via H-1, C-13 APT, FT-IR, MS and elemental analysis. The synthesized novel compounds were studied in terms of structure-activity relationship based on dielectric, thermal stability, and theoretical analysis. Dielectric analysis was carried out in terms of amino acid type and aromatic substituted group (electron-withdrawing or releasing group factor). Amino acid side chain differences make alanine conjugates have higher epsilon \" values compared to glycine conjugates. Thermal stability analysis was performed for the compounds (10 and 16) with the highest dielectric constants. Thermal decomposition activation energies were calculated as 95 kJ mol(-1) and 100 kJ mol(-1) for 10 and 16, respectively. HOMO-LUMO energy levels and other related properties of the target compounds were analyzed and a correlation was observed between HOMO-LUMO energy band gap and dielectric constant.

Juglone (5-hydroxy-1,4-naphthoquinone) (J) is a naphthoquinone structured allelochemical that is mostly found in the roots, leaves, nut-hulls, bark, and wood of walnut (Juglans regia). In this study, the biocompatibility, mechanical, thermal, chemical, morphological, and antimicrobial properties of the poly(lactic acid) (PLA) (w/v)/J (10, 20, 30 mg) electrospun scaffolds were investigated. Based on the results of the study, it was shown that juglone addition increased the antimicrobial properties of the scaffolds against the Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli), compared to the neat PLA film after 24 h of contact time. According to the tensile test results, the addition of J made the scaffolds more flexible but decreased the mechanical strength. The cytotoxicity properties of the J-added scaffolds demonstrated a toxic behavior on the first day of incubation. However, with an increase in the J ratio, the fibroblast cell metabolic activity increased for all incubation periods.

In this study, 10 mg fluconazole (10 FCZ) and 10 mg gentamicin (10 GEN) loaded with 40% polymethylmethacrylate (40% PMMA) fibers were fabricated by electrospinning and the performance of the formulations (40% PMMA, 40% PMMA/10 FCZ, 40% PMMA/10 GEN, and 40% PMMA/10 FCZ/10 GEN) was tested. 10 mg Gentamicin-loaded 40% PMMA fiber mat showed a more significant zone of inhibition against the S. aureus compared to the zone of 40% PMMA/10 GEN/10 FCZ fiber. The biocompatibility test using a human adipose-derived mesenchymal stem cell (MSCs) as a cell model proved that the amount of loaded and released GEN has no toxic effects on the MSCs.