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Infectious illnesses are on the rise in today’s world, with serious consequences for animals, plants, and humans. Several infections, including the human immunodeficiency virus, affect a large number of individuals in various countries, particularly in the poorer portions of contemporary society, and continue to cause a variety of health problems. Viruses are tiny parasitic organisms. They are infectious agents that can only reproduce within a live cell of an organism. Viruses may infect any living organism. For clinical point- of-care applications, early detections for harmful agents such as bacteria, viruses are critical. The possibility of worldwide epidemics as a result of viral propagation emphasizes the importance of creating speedy, precise, and sensitive early detection systems. Furthermore, because certain viruses have a long latent phase and can evolve from one person to another, early detection during the incubation period is critical for improving recovery rates and avoiding pandemics. Nowadays, there has been various bio-based detection systems that have rapid reaction times, user-friendly, cost-effective, and repeatable. In this review, biological molecule-based detection technologies which focus on virus analysis are examined.

Electrospun nanofibers (ESNF) offer us a chance to obtain nanoscale building blocks by adding the desired modification agent to the polymer solution. Here, nanocomposite-based electrospun nanofibers designed for the recognition surface of the developed immunosensor were used for the first time in the determination of CD36. Firstly, graphene oxide (GO) was synthesized from graphite powder (GR), and GO sheets were silanized with different amounts of (3-Aminopropyl)triethoxysilane (APTES). Synthesized GO-APTES nanocomposite and polystyrene (PS) solution were mixed in different ratios to obtain uniform nanofibers without beads. As a result of the amino groups obtained on the surface of the nanofibers, the surface was made ready for covalent immobilization of the Anti-CD36 antibody. The nanofibers obtained under the optimum conditions determined were deposited on the surface of the screen-printed carbon electrode (SPCE) by the electrospinning technique. Then, Anti-CD36 was immobilized on the PS/GO-APTES modified SPCE through covalent bonding and used to prepare the biofunctional surface for the usage of bioelectrochemistry of CD36. The optimum Anti-CD36 con-centration decided to be used in experiments was determined as 10 mu g/mL. The linear detection range of CD36 was from 0.5 to 20 ng/mL, and the detection limit was 0.999 ng/mL. Finally, the developed PS/GO-APTES/Anti-CD36 immunosensor was used for the determination of CD36 in artificial blood serum without any interference effect., Council of Higher Education of Turkey [YOK 100/2000]; Ege University Scientific Research Projects Coordination Unit [FGA-2021-22688], S. ER who is supported in the special subject (Sensor Technologies) thanks The Council of Higher Education of Turkey 100/2000 PhD Project (YOK 100/2000 PhD Project). This study is supported by Ege University Scientific Research Projects Coordination Unit (Project Number: FGA-2021-22688).

Real-time detection of substance use is an approach of high interest leading to the optimization of behavioral interventions and drug abuse intervention. the current methods in use suffer many limitations and need high logistical and laboratory requirements. Biosensors have shown a great potential in overcoming these limitations. in the present study, the electrochemical biosensor composed of a screen-printed electrode (SPE) was designed for the detection of synthetic cannabinoid (SC). Antibody-immobilized magnetic nanoparticles were also used to create a surface on the transducer with magnetic interactions in order to detect JWH-073 as a SC model. the use of immobilized magnetic nanoparticles to create working surfaces makes the electrode a reusable SPE which can be reutilized after the cleansing. To examine and observe any possible changes on the surface due to its interaction with the analyte, different electrochemical techniques such as differential pulse voltammetry, cyclic voltammetry, and electrochemical impedance spectrometry were applied. Based on the obtained results, the linearity of the biosensor was found between 5 and 400 ng/mL, and the detection limit was calculated as 22 ng/mL (n = 6) using the 3 Sb/m formula. the biosensor functionality was studied in the presence of some related interferents that showed lower responses than JWH-073, thus demonstrating the good selectivity of the prepared biosensor. Finally, the sensory platform was used to test synthetic urine sample, and the results were compared with obtained results from liquid chromatography quadrupole time-of-flight mass spectrometry (LC-QTOF/MS), which showed that the proposed method could be utilized to identify abuse drugs., Republic of Turkey, Ministry of DevelopmentTurkiye Cumhuriyeti Kalkinma Bakanligi [2016K121190]; Ege University, Aliye USTER FoundationEge University, This work was funded by Republic of Turkey, Ministry of Development (Project Grant No: 2016K121190). SEM and Chromatographic analyses were performed at EGE MATAL (Ege University/Izmir). Ege University, Aliye USTER Foundation is also acknowledged for the financial support.

BODIPY dyes are strongly fluorescent small molecules widely used in fluorescence sensing various analytes. In this study, 8-chloromethyl-2,6-diethyl-4,4-difluoro-1,3,5,7-tetramethyl-4-bora-3a,4a-diaza-s-indacene (BODIPY-CH2Cl) was successfully synthesized and used as a sensing platform in a 96-well microplate. After synthesis, commercial 96-well microplate surfaces covered with Poly-D-Lysine layer were modified with BODIPY. Glucose oxidase (GOx) was selected as a model enzyme to test the applicability of the BODIPY-coated surface as a fluorescence sensing platform. Since oxygen acts as a quencher for BODIPY, the addition of substrate to modified surfaces caused oxygen depletion and resulted in a quick increase fluorescence intensity. The increments were in proportion to the glucose concentration. Using these data, a linear graph was obtained between 0.0025 and 0.1 mM glucose with a LOD of 2.19 µM. There was no interference effect of some compounds, such as uric acid, ascorbic acid, phenols, and ethanol on sensing. Glucose detection in various complex matrices was carried out. © 2018 Elsevier Ltd

Stabilization of biomolecules on matrices is critically important. Here we constructed composite nanofibers with magnetic features by electro-spinning of magnetic nanoparticles (MNP) in an appropriate polymer matrix on a collector surface for multiple uses. 'Poly(vinylalcohol)-polyethyleneimine/Fe3O4 magnetic nanoparticles' (PVA-PEI/MNP) composite nanofiber was used on the screen printed electrodes (SPE) to serve as a platform for the glucose oxidase (GOx) biofilm as the model biomolecule. To show the potential application of this material as a biosensor component, the resulted biofilm, called 'PVA-PEI/MNP/GOx', was fixed on SPE via a neodymium magnet for the electrochemical detection of glucose at -0.7 V where oxygen consumption due to enzymatic reaction was measured. The main advantage of the obtained magnetic biomembrane is that it allows analysis with a single drop. After step-by-step surface modifications, analytical characterization was performed using various techniques, such as voltammetry, electrochemical impedance spectroscopy, Fourier-transform infrared spectroscopy and X-Ray photoelectron spectroscopy as well as microscopic techniques. The linear range of the PVA-PEI/MNP/GOx surface was found as 0.0125 to 0.5 mM with a limit of detection of 11.5 mu M for glucose as analyte. The application of PVA-PEI/MNP/GOx for glucose detection in synthetic samples was carried out. Data proved the potential use of the 'PVA-PEI/MNP' surface as a biomolecule immobilization platform for disposable biosensor applications.

In this study, poly-?-caprolactone (PCL) and poly(acrylic) acid (PAA)-based electrospun nanofibers were prepared for the immobilization of pyranose oxidase (PyOx) to design a bioelectrochemical detection system. Different amounts of PAA were used to increase hydrophilicity (decreased contact angle) of the PCL electrospun nanofibers. To provide a multipoint attachment side to bind PyOx by covalent bonds, various amounts of high generation (G5) poly(amidoamine) (PAMAM) dendrimer with amino groups were added to the PCL:PAA backbone. To attach PyOx onto the PCL:PAA/PAMAM electrospun nanofibers, glutaraldehyde was used as a homobifunctional crosslinker. Firstly, PCL:PAA ratio was optimized to obtain the best electrospun nanofibers without beads and with decreased contact angle. Then, the effect of the PAMAM amount on the morphology of PCL:PAA and contact angle was tested. The obtained PCL:PAA/PAMAM electrospun nanofiber was characterized by scanning electron microscopy (SEM). Then, the presence of PAMAM in the structure and the success of PyOx immobilization onto PCL:PAA/PAMAM were proven by SEM and an energy dispersive X-ray analyzer (SEMEDX). Finally, PCL:PAA/PAMAM/PyOx was characterized, calibrated, and applied to analyze glucose in samples without any interfering effect of some chemicals. Briefly, the nanofibers modification with dendrimers and the conjugation of PyOx onto formed nanostructures was successfully performed, and a novel electrospun nanofiberbased sensor system was developed for target detection., BAGEP Award of the Science Academy; TUBITAKTurkiye Bilimsel ve Teknolojik Arastirma Kurumu (TUBITAK) [215Z194]; TUBITAK 2209Turkiye Bilimsel ve Teknolojik Arastirma Kurumu (TUBITAK), Acknowledgement This work is supported by the BAGEP Award of the Science Academy and TUBITAK (Project number: 215Z194) . A. Oner, E. Tufek, A. Birol and M. Demir thank to TUBITAK 2209 AProgram for the University Students at Undergraduate Level. Authors thank to Assoc. of Prof. Dr. Murat Yavuz for his valuable helps.

Growing needs in biomedical applications have driven the development of multifunctional nanoparticles towards theranostically-engineered multimodal platforms. Many strategies for point-effective cellular uptake of theranostics have been described. in this report, multifunctional nanostructures were designed and synthesized as a novel theranostic platform. Liposomes were loaded with curcumin as a therapeutic agent and carbon dots (CDs) as a contrast molecule. Anti-CD44 antibodies were bioconjugated on the liposomal surface to obtain an active targeting nanocarrier. After synthesis, the relative characterization of the vesicles was performed using DLS and TEM techniques. in vitro analysis was conducted to investigate the multimodal properties of the theranostic via testing its toxicity, cell uptake, bioimaging, and chemo/radiotherapy applications on two different cell lines. 3D holographic microscopy was employed to track the treatment effects during experimentation. Results indicated that these particles are efficient tools for clinical applications due to their fluorescent characteristic and increased bioperformance., Ege University, Scientific Research FoundationEge University [2017 FEN 007], Ege University, Scientific Research Foundation is acknowledged for the support (Project no: 2017 FEN 007) .

To improve bioavailability and stability of hydrophobic and hydrophilic compounds, nanoemulsions are good alternatives as delivery systems because of their nontoxic and nonirritant nature. Glutathione (GSH) suffers from low stability in water, where its encapsulation in nanoemulsions is a powerful strategy to its stability in aqueous systems. The aim of this study was to obtain nanoemulsions from the hydrophobic/hydrophilic contents of N. sativa seed oil so as to improve GSH stability along with bioavailability of N. sativa seed oil. Then, the prepared nanoemulsions were tested for in vitro hepatoprotective activity against ethanol toxicity. To the best of our knowledge, there is no study on the test of nanoemulsions by the combination of Nigella sativa seed oils and GSH in hepatoprotective activity. Here, nanoemulsions with different contents were prepared using Nigella sativa seed oils. Content analyses and characterisation studies of prepared nanoemulsions were carried out. In order to investigate the protective effects against to ethanol exposure, THLE-2 cells were pretreated with nanoemulsions for 2 h with the maximum benign dose (0.5 mg/mL of nanoemulsions). Ethanol (400 mM) was introduced to pretreated cells and nontreated cells for 48- or 72-h periods, followed by cell viability assay was carried out. Fluorescence microscopy tests revealed the introduction of the nanoemulsions into THLE-2 cells. The findings show that nanoformulations have promising in vitro hepatoprotective effects on the THLE-2 cell line against ethanol exposure. WOS:000644696500016 34104055 Q4

Hybrid materials containing organic and inorganic structures are very important because they have the advantages of each of their components. Intercalation of the organic molecule to inorganic structures such as clay allows the preparation of multifunctional new immobilization matrices that contain both the strength properties of the clays and the properties of the organic molecule such as its functional groups (amine, carboxyl or hydroxyl etc.). in this study, 4-aminothiophenol intercalated montmorillonite (4ATP-Mt) was prepared and used as an immobilization layer for the pyranose oxidase (PyOx) enzyme on a glassy carbon (GC) electrode. Firstly, 4ATP intercalation of Mt was carried out, and the success of intercalation was proven using Fourier-Transform Infrared Spectroscopy (FTIR), X-ray Diffractometer (XRD), and Thermogravimetric Analysis (TGA) techniques. Then PyOx was immobilized using 4ATP-Mt, BSA and glutaraldehyde as a cross-linker on the surface of GC electrodes. To show the coating steps for the preparation of 4ATP-Mt/PyOx biosensors, cyclic voltammetry (CV), differential pulse voltammetry (DPV) and electrochemical impedance spectroscopy (EIS) techniques were applied, and surface morphology was visualized by scanning electron microscopy (SEM). After optimization of working conditions, analytical performance parameters were determined for glucose detection. the 4ATP-Mt/PyOx biosensor exhibited a wide linear concentration range between 0.01 and 0.5 mM (LOD: 1.0 mu M) for glucose. Additionally, the fabricated 4ATP-Mt/PyOx was assayed for the analysis of glucose in artificial body fluids and drinks., Ege University Scientific Research Projects Coordination UnitEge University [16-FBE-023], This work was supported by Ege University Scientific Research Projects Coordination Unit. Project Number: 16-FBE-023.

Aptamers are selective molecules against to various sizes of targets from small molecules to mammalian cells. Here, we reported QDs containing electrochemical aptasensor for the detection of E. coli O157:H7. the electrode surfaces were modified by cysteamine (CysN), which has amine and thiol groups, via self-assembled monolayer formation. the carboxyl-functionalized quantum dots (QD) and aptamers (Apt) were conjugated to cysteamine modified gold electrodes. Linear range for E. coli O157:H7 was from 1 to 102 CFU/mL after incubation on CysN/QD/Apt modified Au surfaces. QDs provide fluorescence surface, so that adhesion of cells was followed using fluorescence microscope. Adhered cells were also imaged by scanning electron microscopy. Finally, cell analysis was carried out in real samples., Aptamerler, küçük moleküllerden memeli hücrelerine kadar çeşitli boyutlardaki hedeflere karşı seçici moleküllerdir. Burada, E. coli O157:H7 dedeksiyonu için QD içeren elektrokimyasal aptasensör rapor edilmiştir. Yüzeyler, amino ve tiyol grupları içeren sisteamin (CysN) ile kendiliğinden oluşan tek tabaka meydana gelişi ile modifiye edildi. Karboksil ile fonksiyonelleştirilen quantum noktalar (QD) ve aptamerler (Apt), sisteaminle modifiye edilmiş altın elektrotlara konjuge edildi. CysN/QD/Apt modifiye edilen Au yüzeylerde inkübasyon sorasında, E. coli O157:H7 için doğrusal aralık 1 to 102 CFU/mL idi. QD floresans yüzeyler sağlar, böylece hücrelerin adezyonu floresans mikroskop kullanılarak takip edildi. Adezyon sonrası hücreler aynı zamanda taramalı electron mikroskobu ile görüntülendi. Son olarak, hücre analizi gerçek örneklerde gerçekleştirildi.

Phenols are among the most problematic organic compounds, which manipulates metabolism of living organisms and pose threat to environment. Detection of total phenol at the lowest allowable concentration is critical, so development of sensitive and easy to use methods have been heavily investigated. Hereby, for the first time, anthracene (Ant) was sequestered into poly(amic acid) (PAA) to form fluorescent and conductive film support for laccase (Lac) immobilization to quantify total phenol content at high specificity and selectivity. Ant-PAA/Lac films were applied to fluorescent and electrochemical quantification of phenol, which provided high sensitivity (LOD 46 μM) and reproducibility (RSD, 0.5%) for the tested 10 phenolic compounds including phenol, catechol, 3-acetominophenol, hydroquinone, L-DOPA, 2,6-dimethylphenyl, syringalzadine, 3,5-dimethoxy-4-hydroxycinnamic acid, 2,5-dimethoxyaniline and guaiacol. The sensor system showed strong rejection to common organic interferent while real sample application revealed the applicability of the sensor. Therefore, the results can call the sensor system, particularly fluorescence-based quantification in 96-well plate, is an alternative approach for high-throughput screening of total phenolic compounds in waste-water at cost-effective manner.

A novel catechol-bearing polypeptide (CtP) was synthesized and used as a component of electrochemical biosensor involving both enzymatic activity and affinity-based sensing systems. Glucose oxidase (GOx) and anti-immunoglobulin G (Anti-IgG) were selected as model biorecognition elements for the selective analysis of glucose and IgG. Step-by-step surface modifications were followed using various techniques such as cyclic voltammetry (CV) and electrochemical impedance spectrometry (EIS) as well as X-ray photoelectron spectroscopy (XPS). Additionally, contact angles were measured in order to observe surface properties. Amperometric measurements using the GOx biosensor were performed at -0.7 V by following the oxygen consumption due to the enzymatic reaction in different glucose concentrations. Affinity-based interactions via IgG sensor were monitored using the differential pulse voltammetry (DPV) technique. As the "surface design with CtP" approach employed herein is generally applicable and easily adaptable to obtain functional matrices for biomolecule immobilization, CtP-coated surfaces can be promising platforms for the fabrication of various biobased sensing systems.

Herein, we report a facile technique to fabricate fluorescent polymeric structure, brilliant-green sequestered poly(amic) acid film (BG-PAA), as enzyme support-material for biosensor applications. The structure and fluorescence properties of the fabricated BG-PAA membrane were investigated using 1 H NMR, scanning electron microscopy (SEM) and fluorescence microscopy. Glucose oxidase (GOx) was used as a model enzyme that immobilized on BG-PAA membrane using glutaraldehyde. The created BG-PAA/GOx membrane was utilized to fabricate dual-purpose as fluorescent and electrochemical biosensors for the determination of glucose in beverages. Utilization of the dissolved oxygen in GOx mediated glucose oxidation resulted in alteration of the measured fluorescence and current intensity. In the fluorescence assay, the decreased concentration of oxygen causes the increased fluorescence intensity due to the elimination of quenching effect of oxygen on BG fluorescence. In amperometric assay, decrease in oxygen concentration was followed at −0.7 V. After optimization of working conditions linearity, limit of detection and repeatability of system were determined. Finally, BG-PAA/GOx was tested to analyze glucose in beverages.

Becer, C. Remzi/0000-0003-0968-6662; Ozcelik, Serdar/0000-0003-2029-0108; Geyik, Caner/0000-0002-8382-2186; Guler Celik, Emine/0000-0003-2381-9775; YILMAZ, GOKHAN/0000-0002-1803-5397; Odaci Demirkol, Dilek/0000-0002-7954-1381, WOS: 000424988400014, Over the past decade, there has been a great deal of interest in the integration of nanotechnology and carbohydrates. The advances in glyconanotechnology have allowed the creation of different bioactive glyconanostructures for different types of medical applications, especially for drug delivery and release systems. Therefore, the use of more efficient biocompatible nanocarriers with high loading capacity, low overall toxicity and receptor-mediated endocytosis specificity is still in focus for the enhancement of the therapeutic effect. Conjugation of sugar derivatives onto gold nanoparticles presents unique properties that include a wide array of assembling models and size-related electronic, magnetic and optical properties. Here, pH-responsive drug-conjugated glycopolymer-coated gold nanoparticles were prepared by functionalization of gold nanoparticles with thiol-terminated glycopolymers and then subsequent conjugation of doxorubicin (DOX). Among the four different glycopolymers, their drug release, physicochemical characterization (spectroscopy, particle size and surface charge) and in vitro bioapplications with four different cell lines were compared. As a result, pH-sensitive drug delivery via sugar-coated AuNPs was performed thanks to hydrazone linkages between glycopolymers and DOX. Comparative viability tests also demonstrated the efficiency of glycopolymer-DOX conjugates by fluorescence cell imaging. The obtained results reveal that AuNP homoglycopolymer DOX conjugates (P4D) have significant potential, especially in human neuroblastoma cells in comparison to cervical cancer cells and lung cancer cells.

Here, the bioconjugation and application of water-soluble quantum dots QDs for targeted cellular imaging were investigated. Human Anti-c-ErbB2 antibodies were bound to QDs for the targeting of these nanostructures towards the cancer cells. QDs and Anti-c-ErbB2/QD bioconjugates were characterized by fluorescence and UV–Vis spectroscopy and hydrodynamic sizing. The effect of QDs and Anti-c-ErbB2/QD bioconjugates on cell viability was evaluated using an MTT assay. To observe targeting efficiency of Anti-c- ErbB2/QD bioconjugates, fluorescence microscopy and was performed. Higher cell affinities were obtained by Anti-c-ErbB2-conjugated QDs which is an evidence that these are well-suited for targeting and imaging of cells., B urada, hedeflenmiş hücresel görüntüleme için suda çözünür kuantum noktaların QD biyokonjugasyonu ve uygulamaları gerçekleştirilmiştir. Kanser hücrelerine nanoyapıların hedeflenmesi için anti-c-ErbB2 antikoru QD’lara bağlanmıştır. QD’lar ve anti-c-ErbB2/QD biyokonjugatları floresans/UV-Görünür bölge spektroskopisi ve hidrodinamik boyut ölçümleri ile karakterize edilmiştir. Hücre canlılığına QD’lar ve antic-ErbB2/QD biyokonjugatlarının etkisi MTT denemeleri kullanılarak gerçekleştirilmiştir. Anti-c-ErbB2/QD biyokonjugatlarının hedefleme etkinliğini gözlemlemek için, floresans mikroskopi kullanılmıştır. Hücreleri görüntüleme ve iyi gerçekleştirilmiş hedeflemenin ispatı olarak anti-c-ErbB2 konjuge edilen QD’lar ile daha yüksek hücre afiniteleri elde edilmiştir

Transition metal oxides provide low cost alternatives to noble metals due to their unique electrocatalytic and electrochromic properties and display strong interactions with noble metal nanoparticles. Present study describes the use of mixed molybdenum and manganese oxide film electrode enriched with platinum nanoparticles to enhance the catalytic performance in the oxygen reduction reaction (ORR). The mixed oxide film, denominated as GCE/MnO x -MoO x /Pt, was co-deposited by pulsed potential deposition technique and then, it was used as an immobilization matrix for the intact bacterial cells. The resulted whole cell biosensor has served as a sensing platform for ethanol detection by monitoring of oxygen consumption as a result of the bacterial metabolism in the presence of the substrate. Following the optimization experiments, GCE/MnOx-MoOx/Pt/ Gluconobacter oxydans biofilm was applied to investigate the analytical characteristics and response time to ethanol as well as operational stability and substrate specificity for other carbon sources. The linear range was found as 0.075–5.0 mM with a response time of 63 s and the developed method was applied to the ethanol determination in alcoholic drinks. Satisfactory recovery figures were obtained in comparison to the standard method.

A novel support material for enzyme immobilization based on cetyltrimethylammonium bromide modified Dellite (CTAB-Del) was successfully synthesized and used to manufacture pyranose oxidase (PyOx) biosensors (CTAB-Del/PyOx). The intercalation of CTAB into Dellite was confirmed by FTIR, XRD and TGA techniques. PyOx was immobilized onto the glassy carbon electrode, via glutaraldehyde crosslinking, by using CTAB-Del as a support. In order to test the analytical performance of CTAB-Del/PyOx biosensors, chronoamperometric measurements were carried out using three electrodes configurations, at a constant potential of −0.7 V in working buffer, under stirring, with successive addition of glucose. The linear response for CTAB-Del/PyOx biosensor ranged from 0.01 to 0.50 mM with an equation of y = 4.42x + 0.004 (R2 = 0.998), and the limit of detection for glucose was calculated to be 0.081 μM (S/N = 3). In order to confirm its practical use, the CTAB-Del/PyOx biosensor was also applied for glucose measurement in various beverages. In addition, the antimicrobial activities of Del and CTAB-Del were screened in vitro by means of the disc diffusion susceptibility test, selecting a yeast, three different Gram-positive, and five different Gram-negative bacteria. The obtained results showed a moderate antibacterial activity of CTAB-Del against Gram-positive bacteria.