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    Graphene: Promises, facts, opportunities, and challenges in nanomedicine

    , Article Chemical Reviews ; Volume 113, Issue 5 , 2013 , Pages 3407-3424 ; 00092665 (ISSN) Mao, H. Y ; Laurent, S ; Chen, W ; Akhavan, O ; Imani, M ; Ashkarran, A. A ; Mahmoudi, M ; Sharif University of Technology
    2013
    Abstract
    Graphene, a two-dimensional (2D) sheet of sp2-hybridized carbon atoms packed into a honeycomb lattice, has led to an explosion of interest in the field of materials science, physics, chemistry, and biotechnology since the few-layers graphene (FLG) flakes were isolated from graphite in 2004. For an extended search, derivatives of nanomedicine such as biosensing, biomedical, antibacterial, diagnosis, cancer and photothermal therapy, drug delivery, stem cell, tissue engineering, imaging, protein interaction, DNA, RNA, toxicity, and so on were also added. Since carbon nanotubes are normally described as rolled-up cylinders of graphene sheets and the controllable synthesis of nanotubes is well... 

    Statistical association mapping of population-structured genetic data

    , Article IEEE/ACM Transactions on Computational Biology and Bioinformatics ; Volume 16, Issue 2 , 2019 , Pages 636-649 ; 15455963 (ISSN) Najafi, A ; Janghorbani, S ; Motahari, A ; Fatemizadeh, E ; Sharif University of Technology
    Institute of Electrical and Electronics Engineers Inc  2019
    Abstract
    Association mapping of genetic diseases has attracted extensive research interest during the recent years. However, most of the methodologies introduced so far suffer from spurious inference of the associated sites due to population inhomogeneities. In this paper, we introduce a statistical framework to compensate for this shortcoming by equipping the current methodologies with a state-of-the-art clustering algorithm being widely used in population genetics applications. The proposed framework jointly infers the disease-associated factors and the hidden population structures. In this regard, a Markov Chain-Monte Carlo (MCMC) procedure has been employed to assess the posterior probability... 

    Serological assays and host antibody detection in coronavirus-related disease diagnosis

    , Article Archives of Virology ; Volume 166, Issue 3 , 2021 , Pages 715-731 ; 03048608 (ISSN) Dowlatshahi, S ; Shabani, E ; Abdekhodaie, M. J ; Sharif University of Technology
    Springer  2021
    Abstract
    Coronaviruses (CoV) are a family of viral pathogens that infect both birds and mammals, including humans. Seven human coronaviruses (HCoV) have been recognized so far. HCoV-229E, -OC43, -NL63, and -HKU1 account for one-third of common colds with mild symptoms. The other three members are severe acute respiratory syndrome (SARS)-CoV, Middle East respiratory syndrome (MERS)-CoV, and SARS-CoV-2. These viruses are responsible for SARS, MERS, and CoV disease 2019 (COVID-19), respectively. A variety of diagnostic techniques, including chest X-rays, computer tomography (CT) scans, analysis of viral nucleic acids, proteins, or whole virions, and host antibody detection using serological assays have... 

    Fabrication of sensitive glutamate biosensor based on vertically aligned CNT nanoelectrode array and investigating the effect of CNTs density on the electrode performance

    , Article Analytical Chemistry ; Volume 84, Issue 14 , June , 2012 , Pages 5932-5938 ; 00032700 (ISSN) Gholizadeh, A ; Shahrokhian, S ; Iraji Zad, A ; Mohajerzadeh, S ; Vosoughi, M ; Darbari, S ; Koohsorkhi, J ; Mehran, M ; Sharif University of Technology
    2012
    Abstract
    In this report, the fabrication of vertically aligned carbon nanotube nanoelectrode array (VACNT-NEA) by photolithography method is presented. Electrochemical impedance spectroscopy as well as cyclic voltammetry was performed to characterize the arrays with respect to different diffusion regimes. The fabricated array illustrated sigmoidal cyclic voltammogram with steady state current dominated by radial diffusion. The fabricated VACNT-NEA and high density VACNTs were employed as electrochemical glutamate biosensors. Glutamate dehydrogenase is covalently attached to the tip of CNTs. The voltammetric biosensor, based on high density VACNTs, exhibits a sensitivity of 0.976 mA mM-1 cm-2 in the... 

    High-performance enzyme-free glucose sensor with Co-Cu nanorod arrays on Si substrates

    , Article Recent Patents on Biotechnology ; Volume 12, Issue 2 , 2018 , Pages 126-133 ; 18722083 (ISSN) Shirinzadeh, H ; Yazdanpanah, A ; Karponis, D ; Aghabarari, B ; Tahmasbi, M ; Seifalian, A ; Mozafari, M ; Sharif University of Technology
    Bentham Science Publishers B.V  2018
    Abstract
    Background: Glucose sensors have been extensively researched in patent studies and manufactured a tool for clinical diabetes diagnosis. Although some kinds of electrochemical enzymatic glucose sensors have been commercially successful, there is still room for improvement, in selectivity and reliability of these sensors. Because of the intrinsic disadvantages of enzymes, such as high fabrication cost and poor stability, non-enzymatic glucose sensors have recently been promoted as next generation diagnostic tool due to their relatively low cost, high stability, prompt response, and accuracy. Objective: In this research, a novel free standing and binder free non-enzymatic electrochemical sensor... 

    Novel microfluidic graphene oxide–protein amperometric biosensor for detecting sulfur compounds

    , Article Biotechnology and Applied Biochemistry ; Volume 66, Issue 3 , 2019 , Pages 353-360 ; 08854513 (ISSN) Ghaemi, A ; Abdi, K ; Javadi, S ; Shehneh, M. Z ; Yazdian, F ; Omidi, M ; Rashedi, H ; Haghiralsadat, B. F ; Asayeshnaeini, O ; Sharif University of Technology
    Wiley-Blackwell Publishing Ltd  2019
    Abstract
    Sulfur compounds are essential for many industries and organisms; however, they cause serious respiratory problems in human beings. Therefore, determination of sulfur concentration is of paramount importance. The research approach in the field of detecting contaminants has led to smaller systems that provide faster and more effective ways for diagnosis purposes. In this study, a novel portable amperometric graphene oxide–protein biosensor platform is investigated. The main characteristic of this structure is the implementation of a microfluidic configuration. With albumin metalloprotein as the biorecognition element, graphene oxide was synthesized and characterized by transmission electron... 

    A selective chemiresistive sensor for the cancer-related volatile organic compound hexanal by using molecularly imprinted polymers and multiwalled carbon nanotubes

    , Article Microchimica Acta ; Volume 186, Issue 3 , 2019 ; 00263672 (ISSN) Janfaza, S ; Banan Nojavani, M ; Nikkhah, M ; Alizadeh, T ; Esfandiar, A ; Ganjali, M. R ; Sharif University of Technology
    Springer-Verlag Wien  2019
    Abstract
    A chemiresistive sensor is described for the lung cancer biomarker hexanal. A composite consisting of molecularly imprinted polymer nanoparticles and multiwalled carbon nanotubes was used in the sensor that is typically operated at a voltage of 4 V and is capable of selectively sensing gaseous hexanal at room temperature. It works in the 10 to 200 ppm concentration range and has a 10 ppm detection limit (at S/N = 3). The sensor signal recovers to a value close to its starting value without the need for heating even after exposure to relatively high levels of hexanal  

    Electrochemical prostate-specific antigen biosensors based on electroconductive nanomaterials and polymers

    , Article Clinica Chimica Acta ; Volume 516 , 2021 , Pages 111-135 ; 00098981 (ISSN) Dowlatshahi, S ; Abdekhodaie, M. J ; Sharif University of Technology
    Elsevier B.V  2021
    Abstract
    Prostate cancer (PCa), the second most malignant neoplasm in men, is also the fifth leading cause of cancer-related deaths in men globally. Unfortunately, this malignancy remains largely asymptomatic until late-stage emergence when treatment is limited due to the lack of effective metastatic PCa therapeutics. Due to these limitations, early PCa detection through prostate-specific antigen (PSA) screening has become increasingly important, resulting in a more than 50% decrease in mortality. Conventional assays for PSA detection, such as enzyme-linked immunosorbent assay (ELISA), are labor intensive, relatively expensive, operator-dependent and do not provide adequate sensitivity.... 

    Cell "vision": Complementary factor of protein corona in nanotoxicology

    , Article Nanoscale ; Volume 4, Issue 17 , 2012 , Pages 5461-5468 ; 20403364 (ISSN) Mahmoudi, M ; Saeedi-Eslami, S. N ; Shokrgozar, M. A ; Azadmanesh, K ; Hassanlou, M ; Kalhor, H. R ; Burtea, C ; Rothen Rutishauser, B ; Laurent, S ; Sheibani, S ; Vali, H ; Sharif University of Technology
    RSC  2012
    Abstract
    Engineered nanoparticles are increasingly being considered for use as biosensors, imaging agents and drug delivery vehicles. Their versatility in design and applications make them an attractive proposition for new biological and biomedical approaches. Despite the remarkable speed of development in nanoscience, relatively little is known about the interaction of nanoscale objects with living systems. In a biological fluid, proteins associate with nanoparticles, and the amount and the presentation of the proteins on their surface could lead to a different in vivo response than an uncoated particle. Here, in addition to protein adsorption, we are going to introduce concept of cell "vision",... 

    Toward single-DNA electrochemical biosensing by graphene nanowalls

    , Article ACS Nano ; Volume 6, Issue 4 , March , 2012 , Pages 2904-2916 ; 19360851 (ISSN) Akhavan, O ; Ghaderi, E ; Rahighi, R ; Sharif University of Technology
    2012
    Abstract
    Graphene oxide nanowalls with extremely sharp edges and preferred vertical orientation were deposited on a graphite electrode by using electrophoretic deposition in an Mg 2+-GO electrolyte. Using differential pulse voltammetry (DPV), reduced graphene nanowalls (RGNWs) were applied for the first time, in developing an ultra-high-resolution electrochemical biosensor for detection of the four bases of DNA (G, A, T, and C) by monitoring the oxidation signals of the individual nucleotide bases. The extremely enhanced electrochemical reactivity of the four free bases of DNA, single-stranded DNA, and double-stranded DNA (dsDNA) at the surface of the RGNW electrode was compared to electrochemical... 

    Efficient protein immobilization on polyethersolfone electrospun nanofibrous membrane via covalent binding for biosensing applications

    , Article Materials Science and Engineering C ; Volume 58 , 2016 , Pages 586-594 ; 09284931 (ISSN) Mahmoudifard, M ; Soudi, S ; Soleimani, M ; Hosseinzadeh, S ; Esmaeili, E ; Vossoughi, M ; Sharif University of Technology
    Elsevier Ltd  2016
    Abstract
    In this paper we introduce novel strategy for antibody immobilization using high surface area electrospun nanofibrous membrane based on ethyl-3-(3-dimethylaminopropyl)-carbodiimide/N-hydroxysuccinimide (EDC/NHS) coupling chemistry. To present the high performance of proposed biosensors, anti-staphylococcus enterotoxin B (anti-SEB) was used as a model to demonstrate the utility of our proposed system. Polymer solution of polyethersolfone was used to fabricate fine nanofibrous membrane. Moreover, industrial polyvinylidene fluoride membrane and conventional microtiter plate were also used to compare the efficiency of antibody immobilization. Scanning electron microscopy images were taken to... 

    A novel model for predicting bioelectrochemical performance of microsized-MFCs by incorporating bacterial chemotaxis parameters and simulation of biofilm formation

    , Article Bioelectrochemistry ; Volume 122 , 2018 , Pages 51-60 ; 15675394 (ISSN) Kalantar, M ; Mardanpour, M. M ; Yaghmaei, S ; Sharif University of Technology
    Elsevier B.V  2018
    Abstract
    Bacterial transport parameters play a fundamental role in microbial population dynamics, biofilm formation and bacteria dispersion. In this study, the novel model was extended based on the capability of microsized microbial fuel cells (MFCs) as amperometric biosensors to predict the cells' chemotactic and bioelectrochemical properties. The model prediction results coincide with the experimental data of Shewanella oneidensis and chemotaxis mutant of P. aeruginosa bdlA and pilT strains, indicating the complementary role of numerical predictions for bioscreening applications of microsized MFCs. Considering the general mechanisms for electron transfer, substrate biodegradation, microbial growth... 

    Mining the potential of label-free biosensors for in vitro antipsychotic drug screening

    , Article Biosensors ; Volume 8, Issue 1 , 2018 ; 20796374 (ISSN) Kilic, T ; Soler, M ; Fahimi Kashani, N ; Altug, H ; Carrara, S ; Sharif University of Technology
    MDPI AG  2018
    Abstract
    The pharmaceutical industry is facing enormous challenges due to high drug attribution rates. For the past decades, novel methods have been developed for safety and efficacy testing, as well as for improving early development stages. In vitro screening methods for drug-receptor binding are considered to be good alternatives for decreasing costs in the identification of drug candidates. However, these methods require lengthy and troublesome labeling steps. Biosensors hold great promise due to the fact that label-free detection schemes can be designed in an easy and low-cost manner. In this paper, for the first time in the literature, we aimed to compare the potential of label-free optical and... 

    Application of single-nucleotide polymorphisms in the diagnosis of autism spectrum disorders: a preliminary study with artificial neural networks

    , Article Journal of Molecular Neuroscience ; Volume 68, Issue 4 , 2019 , Pages 515-521 ; 08958696 (ISSN) Ghafouri Fard, S ; Taheri, M ; Omrani, M. D ; Daaee, A ; Mohammad Rahimi, H ; Kazazi, H ; Sharif University of Technology
    Springer New York LLC  2019
    Abstract
    Autism spectrum disorder (ASD) includes different neurodevelopmental disorders characterized by deficits in social communication, and restricted, repetitive patterns of behavior, interests or activities. Based on the importance of early diagnosis for effective therapeutic intervention, several strategies have been employed for detection of the disorder. The artificial neural network (ANN) as a type of machine learning method is a common strategy. In the current study, we extracted genomic data for 487 ASD patients and 455 healthy individuals. All individuals were genotyped in certain single-nucleotide polymorphisms within retinoic acid-related orphan receptor alpha (RORA), gamma-aminobutyric... 

    An ultrasensitive label free human papilloma virus DNA biosensor using gold nanotubes based on nanoporous polycarbonate in electrical alignment

    , Article Analytica Chimica Acta ; Volume 1048 , 2019 , Pages 31-41 ; 00032670 (ISSN) Shariati, M ; Ghorbani, M ; Sasanpour, P ; Karimizefreh, A ; Sharif University of Technology
    Elsevier B.V  2019
    Abstract
    An impedimetric human papilloma virus (HPV) DNA biosensor based on gold nanotubes (AuNTs) in label free detection was materialized. The AuNTs decorated nanoporous polycarbonate (AuNTs-PC) template as biosensor electrode was fabricated by electrodeposition method. The single strand DNA (ss-DNA) probe was covalently immobilized onto the AuNTs-PC electrode. The hybridization of target sequences with the ss-DNA probe was observed by the electrochemical impedance spectroscopy (EIS). The biosensor showed high selectivity and could differentiate between the complementary, mismatch and non-complementary DNA sequences. The EIS measurements were matched to Randle's equivalent circuit. The... 

    Fabrication of a sensitive and fast response electrochemical glucose sensing platform based on co-based metal-organic frameworks obtained from rapid in situ conversion of electrodeposited cobalt hydroxide intermediates

    , Article Talanta ; Volume 210 , 2020 Shahrokhian, S ; Ezzati, M ; Hosseini, H ; Sharif University of Technology
    Elsevier B.V  2020
    Abstract
    In this study, for the first time, we reported a fast and facile three-step in situ strategy for direct controllable growth of the Co3(BTC)2 MOFs thin films on the GCE, through the rapid conversion of the electrodeposited Co(OH)2 nano-flakes on rGO/GCE, to crystalline rectangular bar-shape structures of MOFs. X-ray diffraction spectroscopy, Fourier transform infrared spectroscopy, field emission scanning electron microscopy, energy dispersive X-ray spectroscopy and elemental mapping analysis used to the structural and morphological characterization of the well-synthesized MOFs. The as-prepared Co3(BTC)2 MOFs were used to construct a non-enzymatic sensing platform for determining the glucose... 

    Design of an effective piezoelectric microcantilever biosensor for rapid detection of COVID-19

    , Article Journal of Medical Engineering and Technology ; Volume 45, Issue 6 , 2021 , Pages 423-433 ; 03091902 (ISSN) Kabir, H ; Merati, M ; Abdekhodaie, M. J ; Sharif University of Technology
    Taylor and Francis Ltd  2021
    Abstract
    Acute respiratory syndrome coronavirus 2 (SARS-CoV-2), also called COVID-19, is one of the most contagious viruses resulting in a progressive pandemic. Since specific antiviral treatments have not been developed yet and its fatal rate is almost high, early and fast detection is critical for controlling the outbreak. In this study, a piezoelectric microcantilever biosensor has been designed for detecting COVID-19 samples directly without requiring preparation steps. The biosensor acts as a transducer and is coated with the related antibody. When the SARS-CoV-2 antigens adsorbed on the microcantilever top surface through their spike proteins, a surface stress due to the mass change would be... 

    Direct growth of metal-organic frameworks thin film arrays on glassy carbon electrode based on rapid conversion step mediated by copper clusters and hydroxide nanotubes for fabrication of a high performance non-enzymatic glucose sensing platform

    , Article Biosensors and Bioelectronics ; Volume 112 , 2018 , Pages 100-107 ; 09565663 (ISSN) Shahrokhian, S ; Khaki Sanati, E ; Hosseini, H ; Sharif University of Technology
    Elsevier Ltd  2018
    Abstract
    The direct growth of self-supported metal-organic frameworks (MOFs) thin film can be considered as an effective strategy for fabrication of the advanced modified electrodes in sensors and biosensor applications. However, most of the fabricated MOFs-based sensors suffer from some drawbacks such as time consuming for synthesis of MOF and electrode making, need of a binder or an additive layer, need of expensive equipment and use of hazardous solvents. Here, a novel free-standing MOFs-based modified electrode was fabricated by the rapid direct growth of MOFs on the surface of the glassy carbon electrode (GCE). In this method, direct growth of MOFs was occurred by the formation of vertically... 

    The field effect transistor DNA biosensor based on ITO nanowires in label-free hepatitis B virus detecting compatible with CMOS technology

    , Article Biosensors and Bioelectronics ; Volume 105 , 15 May , 2018 , Pages 58-64 ; 09565663 (ISSN) Shariati, M ; Sharif University of Technology
    Elsevier Ltd  2018
    Abstract
    In this paper the field-effect transistor DNA biosensor for detecting hepatitis B virus (HBV) based on indium tin oxide nanowires (ITO NWs) in label free approach has been fabricated. Because of ITO nanowires intensive conductance and functional modified surface, the probe immobilization and target hybridization were increased strongly. The high resolution transmission electron microscopy (HRTEM) measurement showed that ITO nanowires were crystalline and less than 50 nm in diameter. The single-stranded hepatitis B virus DNA (SS-DNA) was immobilized as probe on the Au-modified nanowires. The DNA targets were measured in a linear concentration range from 1fM to 10 µM. The detection limit of... 

    Comparison between electrochemical and photoelectrochemical detection of dopamine based on titania-ceria-graphene quantum dots nanocomposite

    , Article Biosensors and Bioelectronics ; Volume 151 , 2020 Ahmadi, N ; Bagherzadeh, M ; Nemati, A ; Sharif University of Technology
    Elsevier Ltd  2020
    Abstract
    In this study, titania-ceria-graphene quantum dot (TC-GQD) nanocomposite was synthesized by hydrothermal method for the first time. The prepared nanomaterials were characterized by XRD, FTIR dynamic light scattering (DLS), FESEM, HRTEM, and EDX spectroscopy along with elemental mapping. The synergistic effect of the nanocomposite components was studied by diffuse reflectance spectroscopy (DRS) and electrical conductivity meter. The results showed that band gap of TC-GQD nanocomposite was shifted to visible lights relative to its components (1.3 eV), and electrical conductivity of the sample was significant increased to 89.5 μS cm−1. After chemical and physical characterization, prepared new...