115 research outputs found
Polymer Film Supported Bimetallic Au–Ag Catalysts for Electrocatalytic Oxidation of Ammonia Borane in Alkaline Media
core-shell Ti-MOF@COFs composites
Antigen galectin-3 (GL-3), a member of beta-galactoside proteins indicates cardiac fibrosis and is a significant biomarker for monitoring heart failure risk and death risk. In this study, a novel sensitive amperometric method for antigen GL-3 detection is developed based on gold nanoparticle-functionalized graphitic carbon nitride nanosheets (g-C3N4@Au NPs) as the sensor platform and Ti-based metal organic framework (Ti-MOF, NH2-MIL-125)@covalent organic frameworks (COFs) composite for the signal amplification. The Ti-MOF@COF composite not only facilitates the penetration of antibody proteins into pore channels, but also the highly stable antigen-antibody interactions. The prepared sensor platform and signal amplification material are characterized by transmission electron microscopy (TEM), scanning electron microscopy (SEM), X-ray diffraction (XRD) method, X-ray photoelectron spectroscopy (XPS), UV-vis spectroscopy, Fourier transform infrared spectroscopy (FTIR), cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). The amperometric technique is utilized to achieve antigen GL-3 detection in plasma samples. The immunosensor demonstrates a wide linearity range (0.0001-20.0 ng mL(-1)) and a low detection limit (0.025 pg mL(-1)). Finally, the prepared immunosensor shows high stability and selectivity under optimum conditions.C1 [Yola, Mehmet Lutfi] Iskenderun Tech Univ, Fac Engn & Nat Sci, Dept Biomed Engn, Antakya, Turkey.[Atar, Necip] Pamukkale Univ, Fac Engn, Dept Chem Engn, Denizli, Turkey
molecularly imprinted polymer
Serotonin (SER) is the important neurotransmitter and its amount in human body can affect the human life. The low level results in anxiety and carcinoid syndrome. Its high level causes crucial toxicity. Molecularly imprinted approach was used in designing a new electrochemical sensor for serotonin (SER) detection in urine samples. The sensor was prepared based on graphene quantum dots (GQDs) incorporated two-dimensional (2D) hexagonal boron nitride (2D-hBN) nanosheets. All nanomaterials' formation and properties were highlighted with scanning electron microscope (SEM), transmission electron microscope (TEM), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD) method, cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). SER imprinted voltammetric sensor was improved in presence of 80.0 mM phenol containing 20.0 mM SER by CV. 1.0 x 10(-12)-1.0 x 10(-8)M and 2.0 x 10(-13)M were founded as the linearity range and the detection limit (LOD). SER imprinted glassy carbon electrode (GCE) was used for urine sample analysis in presence of the other competitor agents such as dopamine (DOP), tryptophan (TRY) and norepinephrine (NOR). The sensor was also investigated for stability and selectivity
Electrochemical PEA Detection in Urine Sample
Phenylethanolamine A (PEA) is used illegally and deposited in animal tissues. Due to the reason, it causes acute poisoning and symptoms of muscular tremors, nervousness. In present article, Ru@Au core-shell nanoparticles (Ru@Au NPs) involved in carbon nitride nanotubes (C3N4 NTs) functionalized graphene quantum dots (GQDs) nanocomposite based molecular imprinted polymer (MIP) was formed for PEA recognition. Firstly, C3N4 NTs@GQDs nanocomposite was prepared by means of hydrothermal treatment. Secondly, this nanocomposite was functionalized with 2-aminoethanethiol (AET) via the affinity of gold-sulfur for binding Ru@Au NPs. After that, PEA imprinted voltammetric sensor was prepared in presence of 100.0 mM phenol as monomer containing 25.0 mM PEA by cyclic voltammetry (CV). All nanomaterials' formation and properties were highlighted with scanning electron microscope (SEM), transmission electron microscope (TEM), X-ray photoelectron spectroscopy (XPS), energy dispersive X-ray analysis (EDX), raman spectroscopy, cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). 1.0 x 10(-12) -1.0 x 10(-9) M and 2.0 x 10(-13) M were founded as the linearity range and the detection limit (LOD). Finally, PEA imprinted glassy carbon electrode (GCE) was used for urine sample analysis in presence of the other competitor agents such as clenbuterol (CLE), ractopamine (RAC) and salbutamol (SAL). In addition, the stability and repeatability of prepared sensor was investigated. (C) 2018 The Electrochemical Society
Determination of Biomolecules/Drug
The interdisciplinary field of materials science involves the discovery and design of new materials. Because of this, materials science has effective interest in the fabrication of biosensors/nanosensors. In this review, we have focused on molecular imprinted electrochemical sensors based nanomaterials such as graphene oxide/carbon nanotubes molecular imprinting has been very effective method to achieve high selectivity and sensitivity for the fabrication of sensors. It is based on the formation of three-dimensional nano-cavities in crosslinking polymer matrix, where the functional and crosslinking monomers are copolymerised in the presence of target molecule (imprint molecule), which acts as a molecular template. In an imprinted polymer, the chemically active moieties of the target molecules are held in position by the highly crosslinked polymeric networks. In addition, the novel nanomaterials such as graphene/carbon nanotubes have many applications in sensor technology. The review presents the recent developments related to molecularly imprinted electrochemical sensors based carbon nanomaterials
Acid, Dopamine, Uric Acid and Tryptophan
The cost-effective technique has been performed on 2-aminoethanethiol (2-AET) functionalized GQDs with mono-metallic and bi-metallic nanoparticles such as rod gold nanoparticles (rAuNPs) and rod gold-platinum nanoparticles (rAu-PtNPs). In present study, the structures of nanomaterials were highligted by transmission electron microscope (TEM), scanning electron microscope (SEM), X-ray photoelectron spectroscopy (XPS), electrochemical impedance spectroscopy (EIS), cyclic voltammetry (CV) and X-ray diffraction (XRD) method. In addition, glassy carbon electrode (GCE) modified with rAu-PtNPs/GQDs nanomaterial (rAu-PtNPs/GQDs/GCE) was utilized in milk sample analysis. (C) 2016 The Electrochemical Society. All rights reserved
Development of cardiac troponin-I biosensor based on boron nitride quantum dots including molecularly imprinted polymer.
The cardiac Troponin-I (cTnI) is one of the subunits of cardiac troponin complexes and a pivotal biochemical marker of acute myocardial infarction (AMI). Due to its myocardial specificity, cTnI is widely used for the diagnosis of AMI diseases. In this study, a novel imprinted biosensor approach based on boron nitride quantum dots (BNQDs) was presented for cTnI detection in plasma samples. Various characterization methods such as scanning electron microscope (SEM), transmission electron microscope (TEM), x-ray diffraction (XRD), cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) were used for all characterizations of nanomaterials. After the characterization analysis, cTnI imprinted electrode was developed in the presence of 100.0 mM pyrrole containing 25.0 mM cTnI. After that, the analytical studies of cTnI in plasma samples were performed by using cTnI imprinted biosensor. The results of the study have revealed that 0.01-5.00 ng mL(-1) and 0.0005 ng mL(-1) were found as the linearity range and the detection limit (LOD). Moreover, the selectivity of cTnI imprinted glassy carbon electrode (GCE) was investigated for plasma sample analysis in the presence of other nonspecific and specific proteins including cardiac myoglobin (MYG), bovine serum albumin (BSA) and cardiac troponin T (cTnT), respectively. Furthermore, the prepared biosensor was examined in terms of stability, repeatability, reproducibility and reusability. Finally, the imprinted biosensor was applied to the plasma samples having high recovery
Sensitive Electrochemical Determination of Chlorpyrifos
Chlorpyrifos (CHL) is organophosphate insecticide and has low water solubility (1.39 mg/L). CHL is known to produce toxic effects by inhibiting the acetylcholinesterase enzyme activity. Because of this, the important health problems occur worldwide. Hence, it is important to detect the concentration of CHL at the sensitive levels in environmental waters. In this study, a novel molecular imprinted voltammetric sensor based on carbon nitride nanotubes (C3N4 NTs) decorated with graphene quantum dots (GQDs) modified glassy carbon electrode (GCE) was developed for determination of CHL. The unique C3N4 NTs@GQDs nanohybrid was synthesized by hydrothermal treatment. CHL imprinted GCE based on C3N4 NTs@GQDs nanohybrid was prepared via electropolymerization process of 100 mM pyrrole as monomer in the presence of phosphate buffer solution (PBS) (pH 7.0) containing 25 mM CHL. The prepared nanomaterials were characterized using scanning electron microscope (SEM), transmission electron microscope (TEM), raman spectroscopy, cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) and X-ray photoelectron spectroscopy (XPS). The linearity range and the detection limit of the method were calculated as 1.0 x 10(-11)-1.0 x 10(-9) M and 2.0 x 10(-12) M, respectively. The sensor was applied to wastewater samples with good selectivity and recovery. The stability and selectivity of the voltammetric sensor were also reported. (C) 2017 The Electrochemical Society. All rights reserved
Sensing of Cypermethrin
Cypermethrin ([RS]-alpha-cyano-3-phenoxybenzyl [1RS, 3RS; 1RS, 3SR]-3-[2,2-dichlorovinyl]-2,2-dimethylcyclopropane carboxylate) is a crucial pyrethroid and it is generally used as poison against crop pests, domestic insects and ectoparasites in farmed fish. A new molecular imprinted sensor approach based on core-shell type nanoparticles (Fe@AuNPs) incorporated two-dimensional (2D) hexagonal boron nitride (2D-hBN) nanosheets was presented for cypermethrin (CYP) detection in wastewater samples. All nanomaterials' formation and properties were highlighted with scanning electron microscope (SEM), transmission electron microscope (TEM), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD) method, energy dispersive X-ray analysis (EDX), cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). CYP imprinted voltammetric sensor was improved in presence of 80.0 mM phenol containing 20.0 mM CYP by CV. 1.0 x 10(-13) -1.0 x 10(-8) M and 3.0 x 10(-14) M were founded as the linearity range and the detection limit (LOD). Finally, CYP imprinted glassy carbon electrode (GCE) was used for wastewater sample analysis in presence of the other competitor agents such as deltamethrin (DEL), tetrametrin (TET) and permethrin (PER). In addition, the prepared sensor was investigated in terms of stability and repeatability. (C) 2018 The Electrochemical Society
carbon electrode
beta-Agonists are illegally consumed in various products such as food and animal and effect the nutrition distribution owing to change of body fat. In addition, they result in acute poisoning and several symptoms such as muscular tremors and nervousness. A new electrochemical approach based on two-dimensional hexagonal boron nitride (2D-hBN) nanosheets decorated functionalized multi-walled carbon nanotubes (f-MWCNTs) was presented for simultaneous determination of beta-agonists such as phenylethanolamine A (PEA), clenbuterol (CLE), ractopamine (RAC) and salbutamol (SAL) in urine samples. X-ray diffraction (XRD) method, Raman spectroscopy, scanning electron microscope (SEM), cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) were used characterizations of nanomaterials. After that, 2D-hBN/f-MWCNTs nanocomposite modified glassy carbon electrode (GCE) was prepared for simultaneous determination of beta-agonists. 1.0 x 10(-12)-1.0 x 10(-8) M and 1.0 x 10(-13) M were founded as the linearity range and the detection limit (LOD) for PEA, CLE, RAC and SAL. Finally, the prepared electrochemical sensor was used for urine sample analysis in presence of ascorbic acid (AA) and uric acid (UA).C1 [Yola, Mehmet Lutfi] Iskenderun Tech Univ, Dept Biomed Engn, Fac Engn & Nat Sci, Antakya, Turkey.[Atar, Necip] Pamukkale Univ, Fac Engn, Dept Chem Engn, Denizli, Turkey
- …