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Gold nanoclusters were synthesized based on the structure of the TetX2 Monooxygenase enzyme to make a nanocluster based on enzyme structure (TetX2@Au-NCs). Kinetic analysis of TetX2@Au-NC nanozyme revealed that the Km values of TetX2@Au-NCs to both H 2 O 2 and TMB chromogenic substrate components are higher in the absence of tetracycline. Additionally, the Vmax of the nanozyme for TMB increased in the presence of tetracycline. Also, in the presence of H 2 O 2 the Vmax of TetX2@Au-NCs nanozyme for tetracycline was decreased. In order to monitor tetracycline, the peroxidation properties of TetX2@Au-NCs were utilized to change the color of the chromogenic substrate (TMB-H 2 O 2 ). The catalytic properties of gold nanoclusters were assessed by chemiluminescence reactions, resulting in changes in light emission. Additionally, fluorescence emission changes of TetX2@Au-NCs were monitored at 450 nm. Three different approach including colorimetry, luminescence, and fluorimetry were used to detect tetracycline with detection times and limits of 15 min and 1.3 mM, 1 min and 1.4 mM, and 30 min and 1.6 mM, respectively. Considering changes in temperature, pH, and even high concentrations of the substrate effects on the performance of enzymes, utilizing the TetX2@Au-NCs nanozyme based on TetX2 monooxygenase enzyme proves to be efficient for detecting higher concentrations with increased accuracy and sensitivity., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Supercritical fluid extraction (SFE) stands out as an incredibly efficient, environmentally conscious, and fast method for obtaining essential oils (EOs) from plants. These EOs are abundant in aromatic compounds that play a crucial role in various industries such as food, fragrances, cosmetics, perfumery, pharmaceuticals, and healthcare. While there is a wealth of existing literature on using supercritical fluids for extracting plant essential oils, there's still much to explore in terms of combining different techniques to enhance the SFE process. This comprehensive review presents a sophisticated framework that merges SFE with EO extraction methods. This inclusive categorization encompasses a range of methods, including the integration of pressurized liquid processes, ultrasound assistance, steam distillation integration, microfluidic techniques, enzyme integration, adsorbent facilitation, supercritical antisolvent treatments, molecular distillation, microwave assistance, milling process and mechanical pressing integration. Throughout this in-depth exploration, we not only elucidate these combined techniques but also engage in a thoughtful discussion about the challenges they entail and the array of opportunities they offer within the realm of SFE for EOs. By dissecting these complexities, our objective is to tackle the current challenges associated with enhancing SFE for commercial purposes. This endeavor will not only streamline the production of premium-grade essential oils with improved safety measures but also pave the way for novel applications in various fields., Competing Interests: Declaration of competing interest The authors declare that they have no any type of conflict of interest., (Copyright © 2024. Published by Elsevier B.V.)

Early detection of the coronavirus is acknowledged as a crucial measure to mitigate the spread of the pandemic, facilitating timely isolation of infected individuals, and disrupting the transmission chain. In this study, we leveraged the properties of synthesized Ag-MOF, including high porosity and increased flow intensity. Electrochemical techniques such as cyclic voltammetry (CV) and differential pulse voltammetry (DPV) were employed to develop an economical and portable sensor with exceptional selectivity for COVID-19 detection. The methodology involves the deposition of Ag-MOF onto the surface of a Glassy Carbon Electrode (GCE), which resulted in a progressive augmentation of electric current. Subsequently, the targeted antibodies were applied, and relevant tests were conducted. The sensor demonstrated the capacity to detect the virus within a linear range of 100 fM to 10 nM, boasting a noteworthy Limit of Detection (LOD) of 60 fM. The entire detection process could be completed in a brief duration of 20 min, exhibiting high levels of accuracy and precision, outperforming comparable techniques in terms of speed and efficacy., Competing Interests: Declaration of competing interest The authors declare that they do not have any competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Here, we report the fabrication of an enzyme-free glucose sensor benefiting from nickel-samarium nanoparticles-decorated MXene layered double hydroxide (MXene/Ni/Sm-LDH). The electrochemical response of the MXene/Ni/Sm-LDH to glucose was studied via cyclic voltammetry (CV). The fabricated electrode has high electrocatalytic activity for glucose oxidation. The voltametric response of the MXene/Ni/Sm-LDH electrode to glucose was investigated by differential pulse voltammetry (DPV) that demonstrated an extended linear range of from 0.001 to 0.1 mM and 0.25-7.5 mM with a detection limit down to 0.24 μM (S/N = 3) and a sensitivity at 1673.54 μA mM -1  cm -2 1519.09 μA mM -1  cm -2 in concentrations of 0.01 mM and 1 mM respectively as well as good repeatability, high stability and applicability for the real sample analysis. Moreover, the as-fabricated sensor was applied to glucose detection in human sweat and showed promising results., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)

In the past several decades, significant efforts have been paid toward photocatalytic degradation of organic pollutants in environmental research. During the past years, titanium dioxide nano-architectures (TiO 2 NAs) have been widely used in water purification applications with photocatalytic degradation processes under Uv/Vis light illumination. Photocatalysis process with nano-architectural design of TiO 2 is viewed as an efficient procedure for directly channeling solar energy into water treatment reactions. The considerable band-gap values and the subsequent short life time of photo-generated charge carriers are showed among the limitations of this approach. One of these effective efforts is the using of oxidation processes with advance semiconductor photocatalyst NAs for degradation the organic pollutants under UV/Vis irradiation. Among them, nano-architectural design of TiO 2 photocatalyst (such as Janus, yolk-shell (Y@S), hollow microspheres (HMSs) and nano-belt) is an effective way to improve oxidation processes for increasing photocatalytic activity in water treatment applications. In the light of the above issues, this study tends to provide a critical overview of the used strategies for preparing TiO 2 photocatalysts with desirable physicochemical properties like enhanced absorption of light, low density, high surface area, photo-stability, and charge-carrier behavior. Among the various nanoarchitectural design of TiO 2 , the Y@S and HMSs have created a great appeal given their considerable large surface area, low density, homogeneous catalytic environment, favorable light harvesting properties, and enhanced molecular diffusion kinetics of the particles. In this review was summarized the developments that have been made for nano-architectural design of TiO2 photocatalyst. Additional focus is placed on the realization of interfacial charge and the possibility of achieving charge carriers separation for these NAs as electron migration is the extremely important factor for increasing the photocatalytic activity., (Copyright © 2022 Elsevier Inc. All rights reserved.)

Graphene-based nanomaterials with remarkable properties, such as good biocompatibility, strong mechanical strength, and outstanding electrical conductivity, have dramatically shown excellent potential in various applications. Increasing surface area and porosity percentage, improvement of adsorption capacities, reduction of adsorption energy barrier, and also prevention of agglomeration of graphene layers are the main advantages of functionalized graphene nanocomposites. On the other hand, Cerium nanostructures with remarkable properties have received a great deal of attention in a wide range of fields; however, in some cases low conductivity limits their application in different applications. Therefore, the combination of cerium structures and graphene networks has been widely invesitaged to improve properties of the composite. In order to have a comprehensive information of these nanonetworks, this research reviews the recent developments in cerium functionalized graphene derivatives (graphene oxide (GO), reduced graphene oxide (RGO), and graphene quantum dot (GQD) and their industrial applications. The applications of functionalized graphene derivatives have also been successfully summarized. This systematic review study of graphene networks decorated with different structure of Cerium have potential to pave the way for scientific research not only in field of material science but also in fluorescent sensing, electrochemical sensing, supercapacitors, and catalyst as a new candidate., (Copyright © 2022 Elsevier Inc. All rights reserved.)

We introduce highly antifouling Polymer-Nanoparticle-Nanoparticle/Polymer (PNNP) hybrid membranes as multi-functional materials for versatile purification of wastewater. Nitrogen-rich polyethylenimine (PEI)-functionalized halloysite nanotube (HNT-SiO 2 -PEI) nanoparticles were developed and embedded in polyvinyl chloride (PVC) membranes for protein and dye filtration. Bulk and surface characteristics of the resulting HNT-SiO 2 -PEI nanocomposites were determined using Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM), and thermogravimetric analysis (TGA). Moreover, microstructure and physicochemical properties of HNT-SiO 2 -PEI/PVC membranes were investigated by scanning electron microscopy (SEM), atomic force microscopy (AFM), and attenuated total reflectance (ATR)-FTIR. Results of these analyses indicated that the overall porosity and mean pore size of nanocomposite membranes were enhanced, but the surface roughness was reduced. Additionally, surface hydrophilicity and flexibility of the original PVC membranes were significantly improved by incorporating HNT-SiO 2 -PEI nanoparticles. Based on pure water permeability and bovine serum albumin (BSA)/dye rejection tests, the highest nanoparticle-embedded membrane performance was observed at 2 weight percent (wt%) of HNT-SiO 2 -PEI. The nanocomposite incorporation in the PVC membranes further improved its antifouling performance and flux recovery ratio (96.8%). Notably, dye separation performance increased up to 99.97%. Overall, hydrophobic PVC membranes were successfully modified by incorporating HNT-SiO 2 -PEI nanomaterial and better-quality wastewater treatment performance was obtained., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2021 Elsevier B.V. All rights reserved.)

Methylation of DNA at carbon 5 of cytosines is the most common epigenetic modification of human genome. Due to its critical role in many normal cell processes such as growth and development, any aberrant methylation pattern in a particular locus may lead to abnormal functions and diseases such as cancer. Development of methods to detect methylation state of DNA which may eliminate labor-intensive chemical or enzymatic treatments has received considerable attention in recent years. Herein, we report a DNA methylation detection procedure based on fluorescence turn-on strategy. Target sequence was selected from Sept9 promoter region that has been reported as one of the most frequently methylated sites in colorectal cancer. Probe DNA was designed to be complementary to this sequence with an additional six cytosines in the middle to form an internal loop to host silver nanoclusters. The fluorescence intensity of the synthesized silver nanoclusters with the duplexes of probe-non-methylated target was significantly different from that of probe-methylated target. The fluorescence enhanced with increasing the methylated DNA concentration with a linear relation in the range of 1.0 × 10 -8  M to 5.0 × 10 -7  M with the detection limit of 8.2 × 10 -9  M, and quenched with non-methylated ones. The method was very specific in the presence of non-complementary sequences with maximum similarity of 40%. Circular dichroism spectra indicated that silver ions significantly affected the structure of methylated and non-methylated DNA into different extents which could further influence the nanocluster fluorescence. Finally, a method was introduced to meet the concerns in the applicability of the proposed method in real situation., Competing Interests: Declaration of competing interest The authors confirm that there are no financial or non-financial conflicts of interest associated with this manuscript that could have influenced its outcomes., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Hydrogel membranes (HMs) are defined and applied as hydrated porous media constructed of hydrophilic polymers for a broad range of applications. Fascinating physiochemical properties, unique porous architecture, water-swollen features, biocompatibility, and special water content dependent transport phenomena in semi-permeable HMs make them appealing constructs for various applications from wastewater treatment to biomedical fields. Water absorption, mechanical properties, and viscoelastic features of three-dimensional (3D) HM networks evoke the extracellular matrix (ECM). On the other hand, the porous structure with controlled/uniform pore-size distribution, permeability/selectivity features, and structural/chemical tunability of HMs recall membrane separation processes such as desalination, wastewater treatment, and gas separation. Furthermore, supreme physiochemical stability and high ion conductivity make them promising to be utilised in the structure of accumulators such as batteries and supercapacitors. In this review, after summarising the general concepts and production processes for HMs, a comprehensive overview of their applications in medicine, environmental engineering, sensing usage, and energy storage/conservation is well-featured. The present review concludes with existing restrictions, possible potentials, and future directions of HMs., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Poloxamers, also called Pluronic, belong to a unique class of synthetic tri-block copolymers containing central hydrophobic chains of poly(propylene oxide) sandwiched between two hydrophilic chains of poly(ethylene oxide). Some chemical characteristics of poloxamers such as temperature-dependent self-assembly and thermo-reversible behavior along with biocompatibility and physiochemical properties make poloxamer-based biomaterials promising candidates for biomedical application such as tissue engineering and drug delivery. The microstructure, bioactivity, and mechanical properties of poloxamers can be tailored to mimic the behavior of various types of tissues. Moreover, their amphiphilic nature and the potential to self-assemble into the micelles make them promising drug carriers with the ability to improve the drug availability to make cancer cells more vulnerable to drugs. Poloxamers are also used for the modification of hydrophobic tissue-engineered constructs. This article collects the recent advances in design and application of poloxamer-based biomaterials in tissue engineering, drug/gene delivery, theranostic devices, and bioinks for 3D printing. STATEMENT OF SIGNIFICANCE: Poloxamers, also called Pluronic, belong to a unique class of synthetic tri-block copolymers containing central hydrophobic chains of poly(propylene oxide) sandwiched between two hydrophilic chains of poly(ethylene oxide). The microstructure, bioactivity, and mechanical properties of poloxamers can be tailored to mimic the behavior of various types of tissues. Moreover, their amphiphilic nature and the potential to self-assemble into the micelles make them promising drug carriers with the ability to improve the drug availability to make cancer cells more vulnerable to drugs. However, no reports have systematically reviewed the critical role of poloxamer for biomedical applications. Research on poloxamers is growing today opening new scenarios that expand the potential of these biomaterials from "traditional" treatments to a new era of tissue engineering. To the best of our knowledge, this is the first review article in which such issue is systematically reviewed and critically discussed in the light of the existing literature., (Copyright © 2020 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.)

Mimicking the native tissue is an ultimate goal in tissue engineering. In this study, conductive chitosan was synthesized by coupling with aniline oligomers, and then conductive nanofibers were fabricated using electrospinning technique to mimic the tissue structure and properties. The conductivity of the resulting biomaterial was adjusted to ca. 10 - 5  S/cm, which can recapitulate electrical properties of the tissue. The structure of nanofiber was evaluated using scanning electron microscopy noticing that the aniline oligomer addition to the system decreased the diameter of the nanofiber because of its hydrophobic nature. Conductive nanofiber exhibited on-demand drug release feature of the conductive webs, signaled by 40% rise in the drug release at 40 min after electrical stimulation in comparison with non-stimulated webs, characteristic of a promising drug release platform. Moreover, biocompatibility evaluation using MTT assay revealed that the conductive substrate provides a higher cellular activity to the platform with respect to non-conductive substrates. Such platforms are the harbingers of the emerging new generation, which can revolutionize the tissue engineering satisfying an enhanced tissue regeneration., Competing Interests: Declaration of competing interest The authors declare no conflict of interest., (Copyright © 2019. Published by Elsevier B.V.)

Microporous and mesoporous minerals are key elements of advanced technological cycles nowadays. Nature-driven microporous materials are known for biocompatibility and renewability. Zeolite is known as an eminent microporous hydrated aluminosilicate mineral containing alkali metals. It is commercially available as adsorbent and catalyst. However, the large quantity of water uptake occupies active sites of zeolite making it less efficient. The widely-used chitosan polysaccharide has also been used in miscellaneous applications, particularly in medicine. However, inferior mechanical properties hampered its usage. Chitosan-modified zeolite composites exhibit superior properties compared to parent materials for innumerable requests. The alliance between a microporous and a biocompatible material with the accompaniment of negative and positive charges, micro/nanopores and proper mechanical properties proposes promising platforms for different uses. In this review, chitosan-modified zeolite composites and their applications have been overviewed., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

Abnormal expression of MicroRNA-21 (miRNA-21) is considered to be a reliable biomarker for the early diagnosis of cancer. In this work, a novel paper based biosensor was fabricated to detect sub-micro molar concentrations of miRNA-21 based on peroxidase mimetic activity of DNA-templated Ag/Pt nanoclusters (DNA-Ag/Pt NCs), which could catalyze the reaction of hydrogen peroxide and 3,3',5,5' tetramethylbenzidine (TMB), to produce a blue color. The Mechanism of reaction was based on the inhibition effect of miRNA-21 on peroxidase-like activity of nanosensor which resulted to quantitative determination of miRNA-21 concentration. It was found that miRNA-21 could be linearly detected in the range from 1-700 pM (A 652  = 0.16x-0.96, R 2  = 0.99; x = -log [miRNA-21]) with a detection limit of 0.6 pM. Moreover, a paper assay was carried out on a Y-shaped paper-based microfluidic device in order to use the distinctive features of micro-channels such as short response time, very low reagent volume, low fabrication cost, etc. After performing paper based assay, a good linear range was observed between 10-1000 pM (y = 0.06x+147.48, R 2  = 0.99; x = [miRNA-21]) with detection limit of 4.1 pM. The practical application of proposed method for detection of miRNA-21 in real sample was assayed in the human urine sample and indicated the colorimetric method had acceptable accuracy., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Although urine cytology and cystoscopy are current gold standard methods in diagnosis and surveillance of Bladder cancer (BC), they have some limitations which necessitates novel diagnostic approaches to compensate their drawbacks. In this regard, Nuclear Matrix Protein 22 (NMP22) is introduced as a potential tumor biomarker for BC detection (FDA approved). NMP22 determination mainly occurs through immunoassay platforms, raising a proper antibody against its antigen. Hence, development of such immunoassays seems crucial. Various bioinformatic tools were harnessed to select a region with lowest variability, highest density for linear and conformational epitopes, lowest post translational modifications, highest antigenicity, best physicochemical properties and reliable transcriptional properties. Subsequently, E. coli BL21 (DE3) and P. pastoris GS115 were applied for exogenous expression. Ultimately, protein purification and quantification was followed by ELISA test for antibody analyses. Both host successfully expressed the antigen, while the E. coli expression was with higher yield. The commercial anti-NMP22 antibodies showed relatively equal detection results. However, the slight better detection for the antigen with P. pastoris origin could be deduced as better structural properties for P. pastoris. These results indicate higher expression yields and lower costs for over-expression of this eukaryotic antigen., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Antioxidants are important to protect and maintain biological barriers, such as the skin. Antioxidant effects are often assessed using clinical trials, however these tests are costly and time consuming. In this work we introduce a skin membrane-covered oxygen electrode (SCOE) as an in vitro tool for monitoring H 2 O 2 and antioxidant reactions in skin. The SCOE gives amperometric response to H 2 O 2 concentrations down to 0.05 mM. More importantly, the electrode allows measurements of polyphenol penetration and reaction with H 2 O 2 in skin. Measurements with SCOE show that lipophilic polyphenols such as quercetin, piceatannol, resveratrol, and plant extract from Plantago major impose their antioxidant effect in skin within 2-20 min. Rutin is however too hydrophilic to penetrate into stratum corneum and therefore cannot deliver its antioxidant effect during similar time interval. The measurements are interpreted considering polyphenol partition-penetration through stratum corneum and the reaction with the H 2 O 2 -catalase system in the skin. The contribution of other enzymes will be addressed in the future., (Copyright © 2019 Elsevier B.V. All rights reserved.)

An efficient voltammetric method for trace level monitoring of methamphetamine (MTM) stimulant drug in the human urine and serum samples is established. This method is based on fast fourier transform square wave voltammetric (FFT-SWV) determination of MTM at a molecularly imprinted polymer (MIP)/multi-walled carbon nanotube (MWCNTs)-modified carbon paste electrode. Voltammetric techniques development for electrochemical assay of MTM is a challenge, due to the weak electroactivity of this drug. Herein, MTM-imprinted nanopolymer was synthesized, using a simple precipitation polymerization method. The resulting polymer, along with MWCNT was then used to fabricate the modified carbon paste electrode which showed a well-defined anodic peak for MTM at about +1.0 V(vs. Ag/AgCl); whereas, the related blank electrode exhibited considerably lower signal at the same conditions. Utilizing the highly efficient MIP, MWCNTs (which increased the charge transfer phenomenon at the electrode surface) and the advanced electrochemical technique of FFT-SWV (which increased the created signal intensity) caused this method to be a high sensitive and selective approach for MTM measurement. In the optimum experimental conditions, the proposed sensor, exhibited linear response range of 1.0 × 10 -8 -1.0 × 10 -4 mol L -1 and the detection limit of 8.3 × 10 -10 mol L -1 with acceptable relative standard deviations (RSD%) for real samples (1.0-3.5%). Herein, the first MIP-based voltammetric sensor for MTM which also exhibits the lowest detection limit, ever reported, is introduced. This approach seems to provide an effective way for rapid screening of MTM in human urine and serum samples., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Early detection of mutation carriers in predisposing genes such as BRCA1 plays an important role in disease prevention. This work developed a quantum dots-based (QDs-based) fluorescence resonance energy transfer (FRET) technique for the detection of single-base mismatch DNA in BRCA1 gene. The FRET between QDs as the donor and silver nanocluster (AgNCs) as the acceptor was designed by the strong interaction between CdTe QDs with appropriate size and dsDNA through binding to its major groove. The dsDNA was formed by the hybridization of ssDNA labeled to AgNCs with target DNA, which introduced CdTe QDs into the major grooves to place the AgNCs in close proximity to the QDs. The complementary and single-base mismatch DNA led to obviously different FRET signals. The FRET signal linearly correlated to the concentration of single-base mismatch DNA in the range of 1.5 × 10 -10 -1.0 × 10 -6  mol L -1 . The proposed method showed a detection limit of 80 pmol L -1 and the sensitivity comparable to the previously reported assays, indicating promising potential for single nucleotide polymorphisms diagnosis in clinical application., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Citrate is currently considered a preferred biomarker for the early stage detection of prostate cancer. In the present work, based on the highly efficient catalytic properties of gold nanoclusters, a novel system for optical determination of citrate was successfully established under optimized conditions. Cysteine-capped gold nanoclusters (Cys-AuNCs) are shown to have an intrinsic peroxidase-mimetic activity. In the presence of H 2 O 2, Cys-AuNCs nanostructures are able to catalyse the oxidation of 3,3',5,5'-tetramethylbenzidine (TMB) with high efficiency to produce a blue dye (with an absorbance maximum at 650 nm). Citrate has carboxylic and hydroxyl groups that can bind with free amino and free carboxyl cysteine groups via hydrogen bonds, thus creating a coating on the surface of the gold nanocluster and inhibiting the cluster oxidation activity. Accordingly, a visual, sensitive and simple colorimetric method using Cys-AuNCs as peroxidase mimetic was developed for detecting citrate. A suitable linear relationship for citrate was obtained for the range of 0.5 to 1000 μM. The limit of detection (LOD) of the proposed method was calculated as 0.1 μM and the relative standard deviation (RSD) was obtained to be less than 4.0%. Moreover, the biosensor was used to perform a paper assay on a Y-shaped microfluidic device and make use of the distinctive features of microchannels such as short response time, very low reagent volume required, low fabrication cost etc. A detection limit of 0.4 μM was achieved through the paper test and a good linear range was observed between 1.0 μM-10 mM. The proposed method was further applied to citrate detection in the human urine sample., (Copyright © 2018 Elsevier B.V. All rights reserved.)

An ultrasensitive and highly selective voltammetric sensor with ultra-trace level detection limit is introduced for RDX determination in water samples. The sensing platform is the nano-sized molecularly imprinted polymer (nano-MIP)/MWCNTs nanocomposite, casted on glassy carbon electrode (GCE). The MIP was synthesized by copolymerization of methacrylic acid and ethylene glycol dimethacrylate in the presence of RDX via precipitation polymerization. The MIP was characterized by scanning electron microscopy (SEM) and fast fourier transform infrared spectroscopy (FT-IR). It was demonstrated that the MIP, coated on the electrode, have the capability to adsorb RDX and increase its related voltammetric signal. This capability was remarkably lower, for the non-imprinted polymer (NIP)-based electrode. The MIP-based electrode signal to RDX is greatly enhanced in the presence of MWCNTs. The sensor showed excellent selectivity to RDX, compared to similar compounds of HMX and TNT. It exhibited two dynamic linear ranges including 0.1-10.0 nmol L -1 and 0.01-1.00 µmol L -1 . The detection limit and relative standard deviation of the sensor were calculated to be 20 pmol L -1 (3S b /m, first curve) and 4.5% (10 nmol L -1 , n = 5), respectively. The utility of the sensor was checked for RDX analysis in water samples which led to satisfactory results., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Here, the construction and characterization of the first immunosensor for highly sensitive and label free detection of Fig mosaic virus (FMV) is reported. The specific antibody against nucleocapsid of the virus was raised and immobilized at the surface of 11-mercaptoundecanoic acid (MUA) and 3-mercapto propionic acid (MPA) modified gold electrode, via carbodiimide coupling reaction. The immunosensor fabrication steps were characterized using cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). The electrochemical detection of FMV was conducted using differential pulse voltammetry in ferri/ferrocyanide solution as a redox probe. The proposed immunosensor exhibited high selectivity, good reproducibility and high sensitivity for FMV detection in a range from 0.1 nM to 1 μM with a detection limit of 0.03 nM. Moreover, good results were obtained for determination of FMV in real samples, indicating the feasibility of the developed immunosensor for detection of fig mosaic disease, without the need for molecular (e.g. PCR) amplification., (Copyright © 2018. Published by Elsevier Inc.)

A luminescence nanosensor has been developed for analysis of Ornidazole in biological samples using graphene-quantum-dot-embedded silica molecular imprinted polymer (GQD-SMIP) as a selective probe for this analyte. The GQD-SMIP was found to possess a strong fluorescent emission at 450 nm upon excitation at 365 nm. This emission was found to linearly quench in the presence of Ornidazole in a concentration range of 0.75 to 30 μM. A detection limit of 0.24 μM was reached using the probe and the sensor was successfully used in the determination of the analyte in plasma samples., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Vaspin, as a newly discovered adipocytokine, can modulate obesity with insulin-sensitizing effects. This study mainly focused on the plasma level of vaspin in insulin resistant rats, which received high-fat diet (HFD) and diazinon (DZN) (70 mg/kg). Upon 30-day experiment, related oxidative stress and inflammatory markers of plasma, the toxic effects of DZN and HFD on the histological structure of the liver, as well as the expression levels of potential genes associated with insulin resistance, phosphatase and tensin homolog (PTEN) and Forkhead box protein O1 (FoxO1) were evaluated. Metabolic parameters implicated to the glucose and insulin statues such as homeostatic model assessment of insulin resistance (HOMA-IR), oral glucose tolerance test (OGTT) and fasting blood glucose (FBG) were determined. DZN significantly inhibited almost 50% of the plasma cholinesterase (ChE) activity. A remarkable increase of MDA level was observed in groups that received DZN and DZN + HFD. Animals treated with DZN or DZN + HFD showed significant changes in reactive oxygen species (ROS) level. The level of plasma tumor Necrosis Factor alpha (TNF-α) was noticeably elevated in the exposed groups. The highest elevation in vaspin level was observed in HFD group followed by DZN treated animals. In all treated groups, insulin level significantly increased and also, the area under the curve (AUC0-180) values of plasma glucose heightened considerably. The histopathological micrographs of HFD + DZN treated group indicated a severe fatty change. The plasma concentration of DZN was significantly higher in the DZN-treated group in comparison to the DZN + HFD group. FoxO1 and PTEN mRNA levels were significantly overexpressed in the DZN and HFD exposed groups. In HFD treated group, PTEN expression significantly increased compared with the DZN and DZN + HFD groups. Consequently, in contrast to oxidative stress and inflammatory biomarkers, vaspin level would be a more reliable diagnostic factor when it comes to the insulin resistance., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Determining methylation state of a particular DNA sequence is an essential task in many epigenetic investigations. Here a facile method based on silver nanocluster (AgNCs) fluorescence enhancement is presented. Target sequences were selected from Sept9 promoter region that its hypermethylation is demonstrated as a reliable biomarker of colorectal cancer. Probe DNA was complementary to a 25 nucleotide of the target region and possessed twelve additional cytosines in the middle to grant the formation of AgNCs. After probe strands were hybridized with methylated and non-methylated targets separately, AgNCs were synthesized, and their fluorescence intensities were recorded. Fluorescence intensity enhanced when the target strands were methylated and quenched when they were non-methylated. The Linear range of fluorescence enhancement was from 1.0 × 10 - 7 M to 5.0 × 10 - 7 M with the detection limit of 7.6 × 10 - 8 M. Sensor specificity was checked with non-complementary strands with the maximum similarity of 40%. Further experiments explored various characteristics of methylated and non-methylated DNAs carrying AgNC and indicated that structure of methylated and non-methylated DNAs was affected differently by silver ions that could then influence AgNC fluorescence. This effect was strongly sequence-dependent, and either fluorescence enhancement or quenching was observed with two different sequences., (Copyright © 2018 Elsevier B.V. All rights reserved.)

In this study, a sensitive fluorescent DNA nanobiosensor has been developed to determine DNA sequence of a well-known tumor suppressor gene, Adenomatous Polyposis Coli (APC). The design of the nanobiosensor was carried out using a synthetic organic ligand as a new fluorophore. The response mechanism of the nanobiosensor was based on DNA hybridization. The new fluorophore was assembled on gold nanoparticles (Au NPs) to enhance the sensitivity of the nanobiosensor response. The fabricated DNA nanobiosensor showed a fluorescence emission at 477 nm by exciting wavelength of 360 nm. By addition of the ssDNA target, the fluorescent emission of the nanobiosensor enhanced linearly in the range from 3.3 × 10 -10 to 1.1 × 10 -9 mol L -1 with detection limit of 1.3 × 10 -11 mol L -1 . The proposed DNA nanobiosensor responded selectively to its complementary strand in comparison with non-complementary and three mismatched bases. The nanobiosensor had also a fast response time with acceptable repeatability. Finally, the performance of the DNA nanobiosensor in biological fluid, serum plasma, was investigated and a satisfactory results were obtained., (Copyright © 2018 Elsevier B.V. All rights reserved.)

New series of triazole-containing 3-phenylcoumarin-lipoic acid conjugates were designed as multi-functional agents for treatment of Alzheimer's disease. The target compounds 4a-o were synthesized via the azide-alkyne cycloaddition reaction and their biological activities were primarily evaluated in terms of neuroprotection against H 2 O 2 -induced cell death in PC12 cells and AChE/BuChE inhibition. The promising compounds 4j and 4i containing four carbons spacer were selected for further biological evaluations. Based on the obtained results, the benzocoumarin derivative 4j with IC 50 value of 7.3 µM was the most potent AChE inhibitor and displayed good inhibition toward intracellular reactive oxygen species (ROS). This compound with antioxidant and metal chelating ability showed also protective effect on cell injury induced by Aβ 1-42 in SH-SY5Y cells. Although the 8-methoxycoumarin analog 4i was slightly less active than 4j against AChE, but displayed higher protection ability against H 2 O 2 -induced cell death in PC12 and could significantly block Aβ-aggregation. The results suggested that the prototype compounds 4i and 4j might be promising multi-functional agents for the further development of the disease-modifying treatments of Alzheimer's disease., (Copyright © 2018 Elsevier Inc. All rights reserved.)

In this study, we developed a colorimetric method which is primarily based on the limited amount of redox in response to the miRNA target analyte binding for the determination of the miRNA, which is used as a biomarker to confirm the clinical diagnosis of cancers such as breast cancer. This method is on the basis of the peroxidase-like property of DNA templated copper nanoclusters (DNA-CuNCs). In this research, it was found that the DNA (poly T) stabilized green emitting CuNCs which exhibited enzyme-like peroxidase activity. After hybridization of miRNA with DNA-CuNCs probe and duplex formation, CuNCs catalyzed the oxidation of the methylene blue (MB) substrate, which can interact easily with DNA/miR-155 heteroduplex. Applying the optimal conditions, the absorbance of MB decreased by increasing the target miRNA-155 with in a dynamic range from 1.0 pM to 10.0 nM down to a detection limit (LOD) of 0.6 pM. The DNA-CuNCs/MB complex was designed to develop a facile, cheap, and fast colorimetric assay for detection of miRNA through MB oxidation by DNA stabilized CuNCs., (Copyright © 2018 Elsevier B.V. All rights reserved.)

The science and engineering of biomaterials have improved the human life expectancy. Tissue engineering is one of the nascent strategies with an aim to fulfill this target. Tissue engineering scaffolds are one of the most significant aspects of the recent tissue repair strategies; hence, it is imperative to design biomimetic substrates with suitable features. Conductive substrates can ameliorate the cellular activity through enhancement of cellular signaling. Biocompatible polymers with conductivity can mimic the cells' niche in an appropriate manner. Bioconductive polymers based on aniline oligomers can potentially actualize this purpose because of their unique and tailoring properties. The aniline oligomers can be positioned within the molecular structure of other polymers, thus painter acting with the side groups of the main polymer or acting as a comonomer in their backbone. The conductivity of oligoaniline-based conductive biomaterials can be tailored to mimic the electrical and mechanical properties of targeted tissues/organs. These bioconductive substrates can be designed with high mechanical strength for hard tissues such as the bone and with high elasticity to be used for the cardiac tissue or can be synthesized in the form of injectable hydrogels, particles, and nanofibers for noninvasive implantation; these structures can be used for applications such as drug/gene delivery and extracellular biomimetic structures. It is expected that with progress in the fields of biomaterials and tissue engineering, more innovative constructs will be proposed in the near future. This review discusses the recent advancements in the use of oligoaniline-based conductive biomaterials for tissue engineering and regenerative medicine applications., Statement of Significance: The tissue engineering applications of aniline oligomers and their derivatives have recently attracted an increasing interest due to their electroactive and biodegradable properties. However, no reports have systematically reviewed the critical role of oligoaniline-based conductive biomaterials in tissue engineering. Research on aniline oligomers is growing today opening new scenarios that expand the potential of these biomaterials from "traditional" treatments to a new era of tissue engineering. The conductivity of this class of biomaterials can be tailored similar to that of tissues/organs. To the best of our knowledge, this is the first review article in which such issue is systematically reviewed and critically discussed in the light of the existing literature. Undoubtedly, investigations on the use of oligoaniline-based conductive biomaterials in tissue engineering need further advancement and a lot of critical questions are yet to be answered. In this review, we introduce the salient features, the hurdles that must be overcome, the hopes, and practical constraints for further development., (Copyright © 2018 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.)