Cengiz Soykan

Amphiphilic and conductive composites are considered notable biomaterials and used as antibacterial agents because they effectively inhibit bacterial growth. In the current study; In the first stage, amphiphilic poly(DEAEMA-co-EMA) copolymers were synthesized from the hydrophilic monomer 2-diethylamino ethylmethacrylate (DEAEMA) and the hydrophobic monomer ethyl methacrylate (EMA) using free radical polymerization. In the second stage, five series composites were prepared at different concentrations using indole conductive monomer in the presence of iron(III) chloride (FeCl3) using the in situ oxidative polymerization technique in poly(DEAEMA-co-EMA) copolymer. The structures of the polymer composites (PCs) were elucidated using FTIR, TGA, SEM, AFM characterization techniques. PCs exhibited significant performance on bacterial biofilm adhesion tested using the Streptococcus mutans by the test tube method (TM). In this study, the 0.006 mg/ml concentration of PC1 reduced the biofilm formation of Streptococcus mutans by 83.199%; PC5, 89.218%; PC3 inhibited 86.078%. 0.003 mg/ml concentration of PC1 prevented S. mutans from forming biofilm by 47.055%; PC5, 71.285%; PC3 was found to inhibit 68.139%. As the concentration and amounth of poly(indole) in the CPs increases, the % antibiofilm effect also increases. From these results, it can be said that PCs as biofilms may be useful materials in antifouling research.

In the current study, in the first stage, amphiphilic poly(2‐diethylamino ethylmethacrylate‐co‐ethyl methacrylate) [Poly(DEAEMA‐co‐EMA)] was synthesized from the 2‐diethylamino ethylmethacrylate (DEAEMA) and the ethyl methacrylate (EMA) using the free radical polymerization method. In the second stage, five series of composites were prepared at different concentrations using the indole conductive monomer in the presence of iron(III) chloride (FeCl ₃ ) using the in situ oxidative polymerization technique in poly(DEAEMA‐co‐EMA) copolymer. Scanning electron microscope and Atomic force microscope images proved the homogeneous structure of the composites, and Fourier transform infrared spectroscopy analysis of the composite has shown that it has been produced successfully. The antimicrobial activity of the prepared poly(DEAEMA‐co‐EMA)/PIN composites was evaluated. Moreover, antioxidant studies of the composites were carried out. The results showed that the enhanced bioactivity of poly(DEAEMA‐co‐EMA)/PIN(90%) composite. In this study, all poly(DEAEMA‐co‐EMA)/PIN composites and polymers showed antibacterial activity against Streptococcus mutans . PCs had more antifungal activity against Aspergillus flavus than PIN, Poly(DEAEMA), and poly(DEAEMA‐co‐EMA). The antimicrobial activity of PCs was enhanced by increasing the permeability of the cell membrane with DEAEMA. It was determined that the antibacterial activity increased in direct proportion to the indole concentration. OSI values of PIN, Poly(DEAEMA), and poly(DEAEMA‐co‐EMA), and PCs ranged between 1.3513 and 0.1183. Highlights: Conductive Polymer Composites are a special commercial polymer composite class due to their biological properties. Discusses morphological properties of poly(DEAEMA‐co‐EMA)/PIN composites. Summarizes antimicrobial and antioxidant activities of poly(DEAEMA‐co‐EMA)/PIN composites. Demonstrate the high antimicrobial activity of Poly(DEAEMA‐co‐EMA)/PIN composites against S. mutans . Determine that Poly(DEAEMA‐co‐EMA)/PIN composites have antioxidant capacity.

In this study, a comprehensive analysis of the CMA2OEM-co-DVB-co-AMPS (2-(bis(cyanomethyl)amino)-2-oxoethyl methacrylate-co-divinylbenzene-co-2-acrylamido-2-methyl-1-propanesulfonic acid) and CMA2OEM-co-DVB-co-VIM (2-(bis(cyanomethyl)amino)-2-oxoethyl methacrylate-co-divinylbenzene-co-vinylimidazole) terpolymers was conducted. The structural and chemical properties of the terpolymers were examined using Fourier transform infrared (FT-IR) spectroscopy, frontier molecular orbital analysis, molecular electrostatic potential (MEP) maps, ¹H, and ¹³C NMR spectroscopy, thermochemistry surface maps (TCSM), toxicity assessments, physical properties, electron localization function (ELF), and total electrostatic potential (ESP) analyses. In silico toxicity analyses, a quantitative structure-activity relationship (QSAR) model was used for Toxicity Estimation Software Tool (TEST) and ProTox 3.0, a web-based virtual toxicity laboratory, was used for oral toxicity prediction. Toxicity estimates using TEST showed that both terpolymers exhibited low toxicity profiles. Oral toxicity prediction emphasizes that CMA2OEM-co-DVB-co-VIM may pose a greater risk compared to CMA2OEM-co-DVB-co-AMPS. In addition, experimental thermal characterization of these terpolymers was also performed. These comprehensive analyses have provided significant insights into the potential applications and functional properties of the terpolymers.

Amfifilik ve iletken kompozitler önemli biyomateryaller olarak kabul edilir ve bakteri üremesini etkili bir şekilde engelledikleri için antibakteriyel ajanlar olarak kullanılır. Bu çalışmada; İlk aşamada, hidrofilik monomer 2-dimetilamino etilmetakrilat (DMAEMA) ve hidrofobik monomer metil metakrilattan (MMA) serbest radikal polimerizasyonu kullanılarak amfifilik poli(DMAEMA-ko-MMA) kopolimeri sentezlendi. İkinci aşamada, poli(DMAEMA-ko-MMA) kopolimerinde in situ oksidatif polimerizasyon tekniği kullanılarak demir(III) klorür (FeCl3) varlığında indol iletken monomeri kullanılarak farklı bileşimlerde beş seri kompozit hazırlandı. Polimer kompozitlerin (PC'ler) yapıları FTIR, TGA, SEM, AFM karakterizasyon teknikleri kullanılarak aydınlatıldı. Kompozitlerin antioksidan özellikleri incelendi. Antioksidan çalışmaları bulguları, kompozitlerde PIN'in oranı arttıkça kompozitlerin antioksidan değerlerinin arttığını gösterdi.

In this study, five compounds belonging to the Polymer composites (PCs) family, have been prepared with different amounts of polyacrylonitrile and polyindole in the composite. The PCs have inherently bactericidal activity, owing to the nitrile and indole groups. Antioxidant activity was assessed by using reducing power activity, superoxide radical scavenging activity and hydroxyl radical scavenging activity. In our study, butylated hydroxy toluene (BHT), ascorbic acid and α‐tocopherol, which are considered synthetic standard antioxidants, were used to compare antioxidant activity. In addition, since it is known that the MDA levels resulting from the oxidation of fats in Saccharomyces cerevisiae yeast cells are inversely proportional to the antioxidant properties, it gave an idea about the in vitro antioxidant properties of the new synthesized PCs. Reducing force capacity, superoxide radical scavenging activity and hydroxyl radical scavenging activity were found to be higher at 100 μg mL⁻¹ concentration compared to 50 μg mL⁻¹ concentration.

The fact that antioxidants scavenge free radicals in the human body and naturally treat many health problems that will occur in this way has increased the consumption of antioxidant-containing foods. However, consumption of artificially prepared antioxidants could cause cancer. Therefore, antioxidants from natural sources are preferred. Quercetin is an antioxidant present in natural samples. In this article, multi-walled carbon nanotubes (MWCNTs), a polymer composite (PC) consisting of a mixture of 15% (by mass) polystyrene (PST), 15% (by mass) polyacrylonitrile (PAN) and 70% (by mass) polyindole (PIN), and semiconducting BiVO₄ were used to prepare electrodes, and then a photosensitive ITO/MWCNTs@PC@BiVO₄-based sensor was fabricated for quercetin detection. Quercetin was analyzed via the photosensitive ITO/MWCNTs@PC@BiVO₄ sensor in 0.1 M phosphate buffered saline (pH 7.4) solutions including various quercetin concentrations. The constructed quercetin sensor displayed a wide linear response between 10 and 200 μM and a limit of detection of 0.133 μM. The developed photosensitive ITO/MWCNTs@PC@BiVO4 demonstrated a high sensitivity (442 µA mM⁻¹ cm⁻²), good reproducibility (relative standard deviation 3.6%), high selectivity and long-term stability (>49 days) towards quercetin sensing. The photoelectrochemical sensor was then applied to detection of quercetin in black tea as a real-life sample. Our study could lead to the development of novel photosensitive PC polyphenol sensors.

In this study, firstly, a thiazole methacrylamide (TMAAm) monomer was synthesized from methacryloyl chloride with 2-aminothiazole. Later on, a series of copolymers of 2-thiazole methacrylamide (TMAAm) with styrene (St) using strange compositions in the feed has been prepared in solution via radical at 70 ^oC with AIBN as initiator. The structure of the copolymers was elucidated by FT-IR, ¹H-NMR, and ¹³C-NMR spectroscopy methods. The compositions of the copolymers were determined from the nitrogen (N) difference according to the elemental analysis results. Monomer reactivity ratios; The r_TMAAm and r_St, Fineman-Ross (FR), Kelen-Tüdös (KT) linear methods, and the error method model in non-linear variables were calculated with the computer program RREVM. The molecular weights and heterogeneity indices of the copolymers were determined by the GPC method. The thermal stability of the copolymers was investigated by thermogravimetry (TG) measurements.

The waste of trace metals are led the pollutions of water, soil and air. That’s why the accurate and sensitive identification of amount of trace metals in food samples and environment are gained importance in analytical chemistry because of their toxicity to human health. Besides, the direct determination of trace metals, presented at very low concentration especially in real samples, is difficult. In this content, before determination of trace metals by instrumental methods can be achieved successfully using separation/preconcentration procedures. The different synthesized chelating polymer resin adsorbents are successfully used for the SPE of trace metals. The trace metals, such as Cu, Cr, Co, Mn, Zn and Fe, are necessary for human health, when it has been taken at certain limits. But, the trace metals, such as Hg, Cd, Pb, Ni and As are toxic metals for the human body. About this, there are studies on the determination of trace elements and mineral in food samples and environment. In this study, new methods in the synthesis of (meth)acrylamides and use as a sorbent in the trace metals extraction was identified.

In this investigation, a solid-phase extraction (SPE) process was improved for selective separation of Cr, Cu, Fe, Mn, Pb and Zn ions on novel ternary composite. These heavy metals were analyzed by flame atomic absorption spectrometry (Flame-AAS). To prepare the novel ternary composite, FeCl₃was used as an oxidant agent in the chemical polymerization technique by formating polystyrene/polyglycidylmethacrylate/polyindole(PSt/PGMA/PIN) [25:25:50]. The structure of novel ternary composite was characterized by FTIR, TGA, X-RD and BET analysis technique. Themorphological surface analysis has been carried out by using SEM and AFM technique. Morphological studies have been show that composite has a smooth surface. To maximum recoveries of heavy metals, the optimum experimental conditions and analytical parameters were searched. These quantitative recoveries of analytes ions were determined at pH7. The detection limits (DL) were found as minimum of 0.9 μg/L and maximum 1.4 μg/L for Cr, Cu, Fe, Mn, Pb and Zn ions. Relative standard deviation (RSD) of the developed SPE process is below 3.3%. This improved SPE process is simple and selective. By the improved extraction method in which PSt/PGMA/PIN ternary composite used as solid phase, analyte ions were determined in certified reference material (CRM), various cosmetic and food products by flame AAS.