Search query: Graphene Oxide ssDNA

Related papers:

abstract: Semiconductor quantum dots/ graphene oxide (QDs/GO) hybrid composites, as emerging materials, have recently attracted intensive attentions in materials science and technology due to their potential applications in electronic and photonic devices. Here, a simple and universal strategy to produce DNA programmed semiconductor quantum dots/ graphene oxide (QDs/GO) hybrid composites with controllable sizes, shapes, compositions, and surface properties is reported. This proof of concept work successfully demonstrates sulfhydryl modified single stranded DNA (S ssDNA) as a "universal glue" can adsorb onto GO easily and provide the growth site to synthesize CdS QDs, CdSe QDs, CdTe QDs and CdTeSe QDs with distinctively sizes, shapes and properties. And, adapting this method, the other graphene oxide based hybrid materials which were easily synthesized in aqueous solution, including oxides, core shell structure QDs and metal nanocrystal, would be possible. This method provided a universal strategy for synthesis and function realization of graphene based nanomaterials.
author_names: Jidong Wang

Zehua Gao

Shengquan He

Penghui Jin

Daoqing Ma

Yabiao Gao

Libin Wang

Shumin Han
title: A universal growth strategy of DNA programmed quantum dots on graphene oxide surface.
venue: Nanotechnology
year: 2020

abstract: We developed a fluorescent aptamer/graphene oxide (GO) based biosensor to detect sulfamethazine (SMZ) residues in animal derived foods. The SMZ bound aptamers were identified and screened with an improved GO SELEX technique using non immobilizing ssDNA library. After seven rounds of selection, six SMZ aptamers were sequenced and analyzed for secondary structure, and their affinity and specificity were assessed by binding assays. The truncated aptamer (SMZ1S: 5' CGTTAGACG 3' with a unique stem loop structure showed the highest affinity K d 24.6 nM) to SMZ and was used to develop a GO based fluorescent aptasensor. The binding mechanism between SMZ1S and SMZ was further analyzed by molecular docking. Under optimal conditions, the fluorescent aptasensor showed low detection limits (0.35 ng/mL) and a wide dynamic linear range (from 2 to 100 ng/mL) The aptasensor was also validated against real samples spiked with SMZ, which showed a fluorescence recovery from 93.9 to 108.8% and a coefficient of variation of 12.7% Taken together, these results suggest that this novel aptasensor can be used to sensitively, selectively, and accurately detect SMZ residues in foods. Schematic illustration of fluorescent aptasensor based on aptamer/graphene oxide complex detection of of SMZ.
author_names: Qiming Kou

Ping Wu

Qi Sun

Chenxi Li

Lei Zhang

Haixing Shi

Juan Wu

Yarong Wang

Xueling Yan

Tao Le
title: Selection and truncation of aptamers for ultrasensitive detection of sulfamethazine using a fluorescent biosensor based on graphene oxide
venue: Analytical and Bioanalytical Chemistry
year: 2020

abstract: Abstract Graphene oxide (GO) membrane, possessing well aligned laminar interlayer channels and oxygen bearing groups, offers great potentials as proton conductor in fuel cells. Yet, the scarcity and non uniform distribution of proton conducting sites in the interlayer channels often lead to low conductivity and hinder the use of GO membranes for proton conduction. Single strand deoxyribonucleic acid (ssDNA) molecules bear abundant phosphate and amidogen groups which can act as proton conducting sites. The sequentially arranged phosphate and amidogen groups are in a linear molecule chain, which accords with the ideal arrangement of proton conducting sites. Herein, we intercalated ssDNA into GO interlayer channels via a pre assembly process to create high efficient proton conducting channels. GO nanosheets offer well aligned 2D physical channels and ssDNA provides large amount of sequentially arranged proton conducting sites, which synergistically enhance proton conduction. The DNA@GO 3 membrane shows a proton conductivity of 564.8 mS cm 1 at 80 degC and 98% RH, which is 4.4 fold higher than that of pristine GO membrane and among the highest of the reported GO based membranes. The H2/O2 single fuel cell performance is improved by nearly 3 folds in terms of maximum power density.
author_names: Pengfei Yang

Hong Wu

Niaz Ali Khan

Benbing Shi

Xueyi He

Li Cao

Xunli Mao

Rui Zhao

Ming Qiu

Zhongyi Jiang
title: Intrinsic proton conductive deoxyribonucleic acid (DNA) intercalated graphene oxide membrane for high efficiency proton conduction
year: 2020

abstract: Abstract A facile strategy has been constructed for the highly efficient discrimination of single nucleotide polymorphisms (SNPs) based on magnetic functionalized graphene oxide (GO@Fe3O4) modified poly(dimethylsiloxane) microchip system coupled with electrochemical detection. A methylene blue labeled single stranded DNA (P1) can complete complementary with target mircoRNA 21 (T1) to form a perfectly matched DNA/RNA heteroduplex (P1T1) while the hybridization of the P1 with single base mismatched sequence of mircoRNA 21 (M1) can form a loose DNA/ms RNA heteroduplex (P1M1) The p stacking interaction between the loose DNA/ms RNA heteroduplex and the GO is much stronger than that of the perfectly matched DNA/RNA heteroduplex. Moreover, GO can enhance the unwinding of unstable DNA/ms RNA through strong interaction between GO and single stranded DNA (ssDNA) and consequently increase the retention time of single base mismatch microRNA 21 in the GO@Fe3O4 based microchip system. Therefore, the GO@Fe3O4 based microchip system exhibited high performance for the separation and detection of microRNA 21 and single base mismatch microRNA 21, which provide a powerful protocol for SNPs discrimination within a short analytical time. More importantly, this platform can be used for other small molecules and proteins assay in various systems by simply changing the sequence of the probe DNA.
author_names: Cheng-Rong Zhang

Ruping Liang

Lu-Lu Wu

Zhijing Wei

Zhi Zhu

Jian-Ding Qiu
title: Discrimination of single nucleotide polymorphisms by magnetic functionalized graphene oxide based microchip system
year: 2020

abstract: The binding reaction of reduced graphene oxide silver nanocomposites (rGO AgNCs) with calf thymus single stranded DNA (ssDNA) was studied by ultraviolet visible absorption, fluorescence spectroscopy and circular dichroism (CD) using berberine hemisulphate (BR) dye as a fluorescence probe. The absorbance of ssDNA increases, but the fluorescence intensity is quenched with the addition of rGO AgNCs. The binding of rGO AgNCs with ssDNA was able to increase the quenching effects of BR and ssDNA, and induce the changes in CD spectra. All of the evidence indicated that there was a relatively strong interaction between ssDNA and rGO AgNCs. The data obtained from fluorescence experiments revealed that the quenching process of ssDNA caused by rGO AgNCs is primarily due to complex formation, i.e. static quenching. The increasing trend of the binding equilibrium constant (Ka) with rising temperature indicated that the binding process was an endothermic reaction. The calculated thermodynamic parameters showed that the binding process was thermodynamically spontaneous, and hydrophobic association played predominant roles in the binding of ssDNA to the surface of rGO AgNCs.
author_names: Xi Li

Lin-qing Yang

Yunfei Wang

Zhongyu Du

Xuyan Mao

Dezhi Sun

Jialei Liu

Yu Zhou

Xiangyu Xu
title: Studies on binding of single stranded DNA with reduced graphene oxide silver nanocomposites.
venue: IET nanobiotechnology
year: 2020

abstract: In this paper, we present a simple and label free colorimetric biosensor for detection of the nopaline synthase (NOS) terminator in genetically modified (GM) plants. The "signal on" colorimetric biosensor was developed using a nanocomposite consisted of gold nanoparticles doped magnetic Fe3O4 nanoparticles (Fe3O4@Au NP) capture probe DNA (cDNA) and hemin functionalized reduced graphene oxide nanosheets (H GN) The nanocomposite was successfully prepared by means of Au S bonds and the strong p interactions between cDNA and H GN. The sensing approach is based on the excellent peroxidase mimicking activity of H GN and its different electrostatic interactions with single stranded DNA (ssDNA) and double stranded DNA (dsDNA) In presence of the target NOS, the cDNA in the nanocomposite will hybridize with its complementary sequence, and form dsDNA structure. Due to the weak p interactions between dsDNA and H GN, a portion of H GN will be released from the surface of Fe3O4@Au NPs and transferred into solution. After magnetic separation was performed, the supernatant was incubated with 3,3',5,5' tetramethylbenzidine (TMB) in the presence of H2O2. The released H GN can catalyze the oxidation reaction of TMB and turn the colorless solution blue. This "signal on" colorimetric biosensor shows a broad linear range of 0.5 100 nM for the target NOS, with a 0.19 nM detection limit. The application of the biosensor for determination of NOS segments in samples of GM and non GM tomatoes shows that it can discriminate between GM and non GM plants. The reliability of the method for samples of NOS spiked GM tomato suggests satisfactory recoveries in the range of 93.6% 94.2%
author_names: Xiaodong Cao

Zihao Xia

Wuwen Yan

Shudong He

Xuan Xu

Zhaojun Wei

Yongkang Ye

Haisong Zheng
title: Colorimetric biosensing of nopaline synthase terminator using Fe3O4@Au and hemin functionalized reduced graphene oxide.
venue: Analytical biochemistry
year: 2020

abstract: A light addressable potentiometric sensor (LAPS) is a kind of silicon based semiconductor sensor, and surface modification is a fundamental problem for its application in biological fields. Graphene oxide (GO) based biochemically activated LAPS were proposed, called GO LAPS. The GO LAPS were applied to monitoring single strand DNA (ssDNA) probe immobilization and its hybridization with complementary ssDNA molecules of different chain lengths (30, 21 and 14 base pairs, respectively) It was discovered that the curves of LAPS' currents versus analyte concentrations for ssDNA probe binding and the target ssDNA hybridization were different. Explanations were proposed based on the semiconductor's surface electric field effect and the electrical properties of ssDNA molecule. Moreover, comparisons between GO LAPS and LAPS without GO modification were carried out. Enhanced response currents of GO LAPS were reported experimentally and analyzed theoretically based on X ray photoelectron spectroscopy (XPS) of GO LAPS. The limitation of target ssDNA monitoring was 1 pM to 10 nM, which suggested that this LAPS based platform could be developed as a sensitive means for short chain ssDNA detection.
author_names: Yunfang Jia

Xuebo Yin

Jia Zhang

Shuang Zhou

Meng Song

Ke-li Xing
title: Graphene oxide modified light addressable potentiometric sensor and its application for ssDNA monitoring.
venue: The Analyst
year: 2012

abstract: In this work, a new platform for effective sensing cysteine (Cys) was developed based on fluorescence resonance energy transfer (FRET) between FAM tagged single stranded DNA (FAM ssDNA) and graphene oxide (GO) Due to the noncovalent assembly between FAM ssDNA and GO, fluorescence quenching of the FAM took place because of FRET. This method relied on the competitive ligation of Ag( by Cys and "cytosine cytosine" (C C) mismatches in a FAM labeled DNA strand of the self hybridizing strand. At first, enough amount of Ag( was introduced to bind "C C" mismatches and form double stranded DNA (dsDNA) which had weak affinity to GO and kept FAM away from GO surface. However, the presence of Cys removed Ag( away from "cytosine Ag( cytosine" (C Ag( C) base pairs, leading to the formation of ssDNA again and FRET, and then fluorescence of the FAM ssDNA was efficiently quenched. The fluorescence intensity decrease was found to be proportional to the increase of concentration of Cys in both aqueous buffer (2 200 nM) and human serum (5 200 nM) and the sensitivity of the proposed method towards Cys was much higher than that of other reported assays for Cys.
author_names: Hongli Liu

Yuhui Wang

Aiguo Shen

Xiaodong Zhou

Jiming Hu
title: Highly selective and sensitive method for cysteine detection based on fluorescence resonance energy transfer between FAM tagged ssDNA and graphene oxide.
venue: Talanta
year: 2012

abstract: A conceptually new class of DNA logic gate and biosensor using the complex of a graphene oxide DNA duplex as a scaffold was reported, achieved by means of formation of the triple stranded DNA structure mediated by Recombinational protein A (RecA) ssDNA nucleoprotein filaments with graphene oxide.
author_names: Longhua Tang

Dongyang Li

Jinghong Li
title: Formation of a graphene oxide DNA duplex based logic gate and sensor mediated by RecA ssDNA nucleoprotein filaments.
venue: Chemical communications
year: 2013

abstract: Rapid detection of foodborne pathogens is crucial as ingestion of contaminated food products may endanger human health. Thus, the objective of this study was to develop a biosensor using reduced graphene oxide carbon nanotubes (rGO CNT) nanocomposite via the hydrothermal method for accurate and rapid label free electrochemical detection of pathogenic bacteria such as Salmonella enterica. The rGO CNT nanocomposite was characterized using Fourier transform infrared spectroscopy, Raman spectroscopy, X ray diffraction and transmission electron microscopy. The nanocomposite was dropped cast on the glassy carbon electrode and further modified with amino modified DNA aptamer. The resultant ssDNA/rGO CNT/GCE aptasensor was then used to detect bacteria by using differential pulse voltammetry (DPV) technique. Synergistic effects of aptasensor was evident through the combination of enhanced electrical properties and facile chemical functionality of both rGO and CNT for the stable interface. Under optimal experimental conditions, the aptasensor could detect S. Typhimurium in a wide linear dynamic range from 101 until 108 cfu mL 1 with a 101 cfu mL 1 of the limit of detection. This aptasensor also showed good sensitivity, selectivity and specificity for the detection of microorganisms. Furthermore, we have successfully applied the aptasensor for S. Typhimurium detection in real food samples.
author_names: Jimmy Nelson Appaturi

Thiruchelvi Pulingam

Kwai Lin Thong

Shalini Muniandy

Noraini Ahmad

Bey Fen Leo
title: Rapid and sensitive detection of Salmonella with reduced graphene oxide carbon nanotube based electrochemical aptasensor.
venue: Analytical biochemistry
year: 2019