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Nonenzymatic sweat-based glucose sensing by flower-like au nanostructures/graphene oxide
, Article ACS Applied Nano Materials ; Volume 5, Issue 9 , 2022 , Pages 13361-13372 ; 25740970 (ISSN) ; Esfandiar, A ; Kazemi, M ; Sharif University of Technology
American Chemical Society
2022
Abstract
The development of a nonenzymatic glucose sensor working in real human body conditions through a noninvasive sampling approach has attracted considerable attention. Hence, this work focuses on the development of a new nonenzymatic glucose sensor based on flower-like Au nanostructures (F-AuNTs) and graphene oxide (GO) as a supporting matrix. The F-AuNTs-GO hybrid was synthesized by simple drop casting of the GO suspension onto the graphite sheet (GS) followed by electrodeposition of F-AuNTs on GO nanosheets at 3 V in a two-electrode system. The electrocatalytic activity of the F-AuNTs-GO/GS sensor toward glucose electrooxidation was initially evaluated in a 0.1 M buffer phosphate solution (pH...
Toward visual chiral recognition of amino acids using a wide-range color tonality ratiometric nanoprobe
, Article Analytica Chimica Acta ; Volume 1231 , 2022 ; 00032670 (ISSN) ; Fahimi Kashani, N ; Morad, R ; Jamshidi, Z ; Hormozi Nezhad, M. R ; Sharif University of Technology
Elsevier B.V
2022
Abstract
Chiral recognition has long been a challenging issue to deal with in biological systems, drug design and food authentication. Implementing nanoparticle-based probes with intrinsic or induced chirality in this field has addressed several issues concerning sensitivity, reliability, rapidness and the cost of chiral sensing platforms. Yet, research into chiral nanoprobes that can be used for visual monitoring of chiral substances is still in its infancy. As part of this study, a visual chiral recognition platform has been developed in which a combination of blue-emitting carbon dots (BCDs) and mercaptopropionic acid-capped CdTe quantum dots (MPA-QDs) with inherent chiroptical activity were...
Determination of spermine and spermidine in meat with a ratiometric fluorescence nanoprobe and a combinational logic gate
, Article Food Chemistry ; Volume 384 , 2022 ; 03088146 (ISSN) ; Bigdeli, A ; Hormozi Nezhad, M. R ; Sharif University of Technology
Elsevier Ltd
2022
Abstract
A ratiometric fluorescent nanoprobe is developed with a wide color variation for visual determination of spermine (SP) and spermidine (SD) in meat samples. The green emission provided from the combination of yellow emissive quantum dots and blue emissive carbon dots turns into pink when SP or SD are present. The results show that the developed sensor has good linearity in the range of 0.5–10 and 0.5–80 µM for SP and SD and suitable detection limits were achieved including 0.2 and 2.1 µM for SP and SD. The probe was highly selective in the presence of amino acids and other biogenic amines. RGB indices were extracted to build a combinational logic gate for visual and simultaneous detection of...
An efficient one-pot synthesis of 1-aminophosphonates
, Article Synthesis (Germany) ; Volume 55, Issue 1 , Volume 55, Issue 1 , 2022 , Pages 121-130 ; 00397881 (ISSN) ; Faghih, S ; Alavi, S ; Naimi Jamal, M. R ; Fattahi, A ; Sharif University of Technology
Georg Thieme Verlag
2022
Abstract
1-Aminophosphonates are valuable compounds with wide range of applications in biological and industry. Various reaction conditions and catalysts have been reported for the synthesis of 1-aminophosphonates via three-component (dialkyl phosphite + aldehyde + amine) or two-component reaction (dialkyl phosphite + imine). Here a solvent-free synthesis of 1-aminophosphonates under very mild reaction conditions is reported. The three-component condensation reactions of dialkyl phosphite, carbonyl compound, and an amine gave 1- aminophosphonates in good to excellent yields under solvent- and catalyst-free conditions at ambient temperature. Hydrophosphorylation of imines in the presence of dialkyl...
Catalytic reduction of nitroarenes and Suzuki-Miyaura reactions using Pd complex stabilized on the functionalized polymeric support
, Article Chemical Physics Letters ; Volume 793 , 2022 ; 00092614 (ISSN) ; Pourmorteza, N ; Yousefi, A ; Esperi, M ; Sharif University of Technology
Elsevier B.V
2022
Abstract
The significance of aromatic amines as crude substances in diverse applications has attracted extensive consideration in the field of economic procedures for the reduction of nitroarenes. Also, the formation of Carbon–Carbon bond as a dominant step in the structure of complex molecules is an important phenomenon in chemical reactions. Improvements of eco-friendly methodologies for reduction process and Carbon–Carbon bond formation have been noticeable. The present work represents through a capable heterogeneous Pd catalyst, the reduction of nitroarenes to the corresponding amines in the presence of N2H4 as a weak hydrogen donor reagent in the room temperature and solvent-free condition was...
Detection of dopamine receptors using nanoscale dendrimer for potential application in targeted delivery and whole-body imaging: synthesis and in vivo organ distribution
, Article ACS Applied Bio Materials ; Volume 5, Issue 4 , 2022 , Pages 1744-1755 ; 25766422 (ISSN) ; Aminzadeh Jahromi, N ; Ali, V ; Ebrahimpour, A ; Salehian, E ; Shafiee Ardestani, M ; Seyedhamzeh, M ; Ahmadi, S ; Sharifi, E ; Ashrafizadeh, M ; Rabiee, N ; Makvandi, P ; Sharif University of Technology
American Chemical Society
2022
Abstract
Dopamine is one of the most important neurotransmitters released by neurons in the central nervous system, and a variety of neurological illnesses and mental disorders are associated with impairments in the secretion and functionality of dopamine. Dopamine, depending on the type of receptors, can act as a stimulant or an inhibitor. In this study, dendrimer-conjugated dopamine was utilized as a chelating agent for Technetium-99m to investigate the organ distribution of this compound in vivo using the single-photon emission computed tomography (SPECT) technique. For this purpose, dendrimers were synthesized using polyethylene glycol diacid and citric acid precursors, and dopamine was...
Biological activated carbon process for biotransformation of azo dye carmoisine by klebsiella spp
, Article Environmental Technology (United Kingdom) ; Volume 43, Issue 18 , 2022 , Pages 2713-2729 ; 09593330 (ISSN) ; Bagheri Lotfabad, T ; Heydarinasab, A ; Yaghmaei, S ; Mohseni, F. A ; Sharif University of Technology
Taylor and Francis Ltd
2022
Abstract
The feasibility of employing the biological activated carbon (BAC) process to debilitate azo dye Carmoisine by Klebsiella spp. was investigated. Plate assay revealed the capability of Klebsiella spp. for removal of Carmoisine via degradation. Kinetic parameters were measured for Carmoisine debilitation by Klebsiella spp. using the suspended anaerobic process. Two types of granular and rod-shaped activated carbon were used to form the biological beds in order to study the Carmoisine debilitation in batch processes. Scanning electron microscopy (SEM) and confocal laser scanning microscopy (CLSM) were used to indicate the colonization and biofilm formation of bacteria grown on activated carbon...
Effectively exerting the reinforcement of polyvinyl alcohol nanocomposite hydrogel via poly(dopamine) functionalized graphene oxide
, Article Composites Science and Technology ; Volume 217 , 2022 ; 02663538 (ISSN) ; Pircheraghi, G ; Nazockdast, H ; Sharif University of Technology
Elsevier Ltd
2022
Abstract
Nature-inspired coating with polydopamine (PDA) is a promising way to improve the performance of graphene oxide (GO) based nanocomposites due to its high ability to enhance interactions in matrix-disperse systems. Here, we examined the capability of two types of PDA to develop the reinforced polyvinyl alcohol (PVA)/GO hydrogels. In the first mode, dopamine hydrochloride was polymerized as nanoparticles and then incorporated into PVA solution with GO nanoplatelets (P-NG hydrogel). In the second mode, polydopamine was polymerized in the presence of GO nanoparticles to obtain PDA surface-modified GO and then PVA nanocomposite hydrogel (P-CG sample). Rheological and tensile findings revealed...
Study on the preparation and properties of polyamide/chitosan nanocomposite fabricated by electrospinning method
, Article Journal of Polymers and the Environment ; Volume 30, Issue 2 , 2022 , Pages 644-652 ; 15662543 (ISSN) ; Fazeli, F ; Nuge, T ; Abdoli, O ; Moghaddam, S ; Sharif University of Technology
Springer
2022
Abstract
The principal intention of this work is to fabricate and characterize the polyamide/chitosan nanocomposite by a novel single solvent method through the electrospinning procedure. The thermal properties and morphology of prepared nanocomposite are studied by thermogravimetric analysis (TGA) and field-emission scanning electron microscopy (FE-SEM). TGA exposed that the primary decomposition temperature is reduced with rising of chitosan content in the nanocomposites and origin disintegration temperature for polyamide/chitosan nanocomposites is perceived to be in the range from 300 to 500 °C. Also, FE-SEM images demonstrated that the nanofibers of chitosan have good adhesion on the matrix and...
A facile one-pot, four-component synthesis of (Z)-isomer of rhodanine-oxindole derivatives under environmentally benevolent conditions
, Article Synthetic Communications ; Volume 52, Issue 2 , 2022 , Pages 175-184 ; 00397911 (ISSN) ; Aghamiri, B ; Jalalinik, M ; Sharif University of Technology
Taylor and Francis Ltd
2022
Abstract
Herein, an efficient and sustainable one-pot, four-component access to rhodanine-oxindole derivatives is achieved by a reaction between primary amines, carbon disulfide, ethyl chloroacetate, and cyano-substituted alkenyl oxindoles. The reaction was conducted without any harsh conditions as well as exhausting workup in polyethylene glycol (PEG) as a green solvent at room temperature and delivered rhodanine-oxindole products in high yield. This publication is the first easy protocol to be reported for the rapid construction of new rhodanine-oxindole derivatives at room temperature without harsh conditions and via multicomponent reaction. © 2021 Taylor & Francis Group, LLC
Copper(ii) ions supported on functionalized graphene oxide: an organometallic nanocatalyst for oxidative amination of azolesviaC-H/C-N bond activation
, Article New Journal of Chemistry ; Volume 45, Issue 6 , 2021 , Pages 3242-3251 ; 11440546 (ISSN) ; Mahmoodi Hashemi, M ; Roknizadeh, M ; Nasiri, S ; Ramazani Saadatabadi, A ; Sharif University of Technology
Royal Society of Chemistry
2021
Abstract
Graphene oxide (GO) was chemically modified withpara-aminobenzoic acid (PABA) to immobilize copper(ii) ions on its surface and used as a nanocatalyst for the oxidative C(sp2)-H bond amination reaction. A practical method to prepare Cu2+supported onpara-aminobenzoic acid grafted on GO was reported. The prepared Cu2+@GO/PABA was characterized by FT-IR, XRD, SEM, AFM, TEM, UV-Vis, and ICP techniques. The results showed that the morphology, distribution, and loading of copper ions could be well-adjusted by grafting of PABA on GO. Moreover, just 2 mol% of Cu2+@GO-PABA could catalyze the C-H activation reaction of benzoxazole and benzothiazole with secondary amines in >94% yields. Also, the...
Study on the Preparation and Properties of Polyamide/Chitosan Nanocomposite Fabricated by Electrospinning Method
, Article Journal of Polymers and the Environment ; 2021 ; 15662543 (ISSN) ; Fazeli, F ; Nuge, T ; Abdoli, O ; Moghaddam, S ; Sharif University of Technology
Springer
2021
Abstract
The principal intention of this work is to fabricate and characterize the polyamide/chitosan nanocomposite by a novel single solvent method through the electrospinning procedure. The thermal properties and morphology of prepared nanocomposite are studied by thermogravimetric analysis (TGA) and field-emission scanning electron microscopy (FE-SEM). TGA exposed that the primary decomposition temperature is reduced with rising of chitosan content in the nanocomposites and origin disintegration temperature for polyamide/chitosan nanocomposites is perceived to be in the range from 300 to 500 °C. Also, FE-SEM images demonstrated that the nanofibers of chitosan have good adhesion on the matrix and...
Nano cobalt-copper ferrite catalyzed regioselective α-C(sp3)–H cyanation of amines: Secondary, tertiary, and drug molecules
, Article Catalysis Communications ; Volume 149 , 2021 ; 15667367 (ISSN) ; Pourkaveh, R ; Heidarian, M ; Sharif University of Technology
Elsevier B.V
2021
Abstract
Oxidative cyanation of sp3C–H bonds at the α position of amines was achieved using CoCuFe2O4 as a catalyst and NaCN as an inexpensive cyanide source at room temperature. CoCuFe2O4 was found to be an active catalyst for Csp [3]-Csp coupling, efficiently delivering valuable α-aminonitriles from tertiary/secondary amines in good yields. The corresponding products were obtained with high selectivity toward α position. In addition, functional group tolerance offered the opportunity for application in late-stage functionalization of biologically active molecules. This transformation proceeds convenient on a gram-scale, and the catalyst can be reused for several runs with consistent catalytic...
Providing Multicolor Plasmonic Patterns with Au@Ag Core-Shell Nanostructures for Visual Discrimination of Biogenic Amines
, Article ACS Applied Materials and Interfaces ; Volume 13, Issue 17 , 2021 , Pages 20865-20874 ; 19448244 (ISSN) ; Ghasemi, F ; Bigdeli, A ; Hormozi Nezhad, M. R ; Sharif University of Technology
American Chemical Society
2021
Abstract
Biogenic amines (BAs) are known as substantial indicators of the quality and safety of food. Developing rapid and visual detection methods capable of simultaneously monitoring BAs is highly desired due to their harmful effects on human health. In the present study, we have designed a multicolor sensor array consisting of two types of gold nanostructures (i.e., gold nanorods (AuNRs) and gold nanospheres (AuNSs)) for the discrimination and determination of critical BAs (i.e., spermine (SM), tryptamine (TT), ethylenediamine (EA), tyramine (TR), spermidine (SD), and histamine (HT)). The design principle of the probe was based on the metallization of silver ions on the surface of AuNRs and AuNSs...
Biological activated carbon process for biotransformation of azo dye Carmoisine by Klebsiella spp
, Article Environmental Technology (United Kingdom) ; 2021 ; 09593330 (ISSN) ; Bagheri Lotfabad, T ; Heydarinasab, A ; Yaghmaei, S ; Mohseni, F. A ; Sharif University of Technology
Taylor and Francis Ltd
2021
Abstract
The feasibility of employing the biological activated carbon (BAC) process to debilitate azo dye Carmoisine by Klebsiella spp. was investigated. Plate assay revealed the capability of Klebsiella spp. for removal of Carmoisine via degradation. Kinetic parameters were measured for Carmoisine debilitation by Klebsiella spp. using the suspended anaerobic process. Two types of granular and rod-shaped activated carbon were used to form the biological beds in order to study the Carmoisine debilitation in batch processes. Scanning electron microscopy (SEM) and confocal laser scanning microscopy (CLSM) were used to indicate the colonization and biofilm formation of bacteria grown on activated carbon...
Preparation of amine–modified lignin and its applicability toward online micro–solid phase extraction of valsartan and losartan in urine samples
, Article Journal of Chromatography A ; Volume 1643 , 2021 ; 00219673 (ISSN) ; Zeinali, S ; Bagheri, H ; Sharif University of Technology
Elsevier B.V
2021
Abstract
In the present work, with the focus on an environmentally–friendly approach, some gels were prepared by synthesizing amine–modified lignin, extracted from sugarcane bagasse, and further esterification and subsequent freeze–drying. These lignin–based gels were implemented as extractive phases in an online micro–solid phase extraction (μSPE) setup in conjunction with high performance liquid chromatography (HPLC) with UV detector. The developed method was used for analytical determination of valsartan and losartan in urine samples. To study the effect of the functionalization process, the efficiency of the unmodified lignin and the functionalized lignin were compared both in the absence and the...
Photoluminescent carbon quantum dot/poly-L-Lysine core-shell nanoparticles: A novel candidate for gene delivery
, Article Journal of Drug Delivery Science and Technology ; Volume 61 , 2021 ; 17732247 (ISSN) ; Mofazzal Jahromi, M. A ; Abdoli, A ; Mohammad Beigi, H ; Fatahi, Y ; Nourizadeh, H ; Zare, H ; Kiani, J ; Radmanesh, F ; Rabiee, N ; Jahani, M ; Mombeiny, R ; Karimi, M ; Sharif University of Technology
Editions de Sante
2021
Abstract
Cationic polymers such as poly-L-lysine (PLL) are able to interact electrostatically with DNA to produce polymeric systems with nanometric diameters due to the neutralization and accumulation of DNA. This study integrates the outstanding properties of carbon quantum dots (CQDs) with PLL to develop a novel gene delivery vehicle with a core-shell hybrid nanostructure. The CQD/PLL core-shell nanoparticles (NPs) were, therefore, synthesized in such a way that they had narrow size distribution and an average diameter under 10 nm, both of which were confirmed by dynamic light scattering (DLS) and transmission electron microscopy (TEM). Fourier transform infrared (FTIR) spectroscopy exhibited that...
Application of NaYF4:Yb/Er/Tm UCNPs in Array-Based Sensing of Neurotransmitters: From a Single Particle to a Multichannel Sensor Array
, Article ACS Applied Materials and Interfaces ; 2020 ; Bigdeli, A ; Hormozi Nezhad, M. R ; Sharif University of Technology
American Chemical Society
2020
Abstract
A novel multichannel sensor array has been designed using a single, yet multiemissive lanthanide-doped upconversion nanoparticle (UCNP). The energy levels of lanthanide ions gave rise to several emission bands which were exploited as individual sensor elements for the recognition of four important neurotransmitters (NTs): dopamine, norepinephrine, levodopa, and serotonin. At alkaline conditions, the oxidation products of these NTs quenched the fluorescence emissions of UCNPs with different quenching degrees. The resulting fingerprint multichannel emission profiles from NaYF4:Yb/Er/Tm UCNPs allowed the discrimination of NTs with excellent accuracy. The recognition was further verified in...
Comparison between electrochemical and photoelectrochemical detection of dopamine based on titania-ceria-graphene quantum dots nanocomposite
, Article Biosensors and Bioelectronics ; Volume 151 , 2020 ; 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...
Surface/edge functionalized boron nitride quantum dots: Spectroscopic fingerprint of bandgap modification by chemical functionalization
, Article Ceramics International ; Volume 46, Issue 1 , 2020 , Pages 978-985 ; Shayeganfar, F ; Hasanzadeh Azar, M ; Simchi, A ; Sharif University of Technology
Elsevier Ltd
2020
Abstract
Promising properties of boron nitride nanomaterials such as their chemical, thermal, and mechanical stability have made them suitable materials in a various range of applications. However, their low electrical conductivity and wide bandgap, particularly in the case of boron nitride quantum dots (BNQDs), have given rise to severe limitations. Efforts on bandgap engineering through doping and surface functionalization have gained little success due to their high thermodynamic stability and inertness. Herein, we present a novel approach to functionalize BNQDs by hydroxyl, methyl, and amine functional groups aiming to adjust the electronic structure. The successful exfoliation is demonstrated by...