Publications by authors named "Venkataraman Dharuman"

15 Publications

  • Page 1 of 1

Structure and dynamics of poly(methacrylic acid) and its interpolymer complex probed by covalently bound rhodamine-123.

Spectrochim Acta A Mol Biomol Spectrosc 2021 Mar 12;248:119166. Epub 2020 Nov 12.

Department of Bioelectronics and Biosensors, Alagappa University, Karaikudi 630003, India.

The dynamics and structural characteristics of polymethacrylic acid bound rhodamine-123 (PMAA-R123) and its interpolymer complex formed through hydrogen bonding between the monomeric units with poly(vinylpyrrolidone) were investigated using single molecular fluorescence studies. The time resolved fluorescence anisotropy decay of PMAA-R123 under acidic pH exhibits an associated anisotropy decay behavior characteristic of two different environments experienced by the fluorophore with one shorter and another longer rotational correlation time. The anisotropy decay retains normal bi-exponential behavior under neutral pH. Fluorescence correlation spectroscopic investigation reveals that the attached fluorophore undergoes hydrolysis under basic condition which results in the release of the fluorophore from the polymer backbone. Shrinkage in the hydrodynamic radius of PMAA is observed on addition of the complementary polymer PVP which is attributed to the formation compact solubilized nanoparticle like aggregates. The size of particle further decreases on the addition of NaCl. The detailed results show that these complexes have potential for use as drug-delivery system under physiological conditions.
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http://dx.doi.org/10.1016/j.saa.2020.119166DOI Listing
March 2021

Platinum and zinc oxide modified carbon nitride electrode as non-enzymatic highly selective and reusable electrochemical diabetic sensor in human blood.

Bioelectrochemistry 2021 Feb 2;137:107645. Epub 2020 Sep 2.

Molecular Electronics Laboratory, Department of Bioelectronics and Biosensors, Alagappa University, Karaikudi 630 003, India. Electronic address:

Development of non-enzymatic glucose sensor is essential to reduce the cost of diabetes regular monitoring. Here, graphitic carbon nitride (g-CN) is modified with platinum and zinc oxide for non-enzymatic electrochemical glucose sensing in physiological conditions for the first time in the literature. The interactions between Pt, g-CN and the ZnO are studied using different physicochemical characterization techniques. The Electrochemical glucose sensing at the ZnO-Pt-gCN occurs at low applied potential of +0.20 V (vs. Ag/AgCl) with high sensitivity 3.34 μA/mM/cm and fast response (5 s) time. This sensor exhibited a wide linear range 0.25-110 mM with lower limit of detection of 0.1 µM. The architectured sensor was evaluated in human blood, serum and urine samples. The sensor is 4 time reusable in whole blood without activity deterioration. This reusable surface helps to reduce the cost of strip.
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http://dx.doi.org/10.1016/j.bioelechem.2020.107645DOI Listing
February 2021

Electrochemical label free sensing of human IgG - Protein A interaction.

Food Chem 2021 Mar 18;339:127881. Epub 2020 Aug 18.

Molecular Electronics Laboratory, Department of Bioelectronics and Biosensors, Science Campus, Alagappa University, Karaikudi 630 003, India. Electronic address:

A novel and rapid Electrochemical Immunosensing platform was developed for the direct sensing of antibody human immuno globulin gamma (IgG) interaction with virulence factor of S. aureus, staphylococcal protein A (SpA) in the presence of electroactive redox couple ferri/ferro cyanide (K/K[Fe(CN)]). The receptor SpA was attached to BioPE-DOTAP binary lipid bilayer tethered on alkane thiol molecular cushions. Atomic force microscopy (AFM), High-resolution transmission electron microscope (TEM), Fourier-transform infrared spectroscopy (FT-IR), dynamic light scattering (DLS) techniques were used to study the molecular interactions. The AFM images showed array like formation of BioPE-DOTAP on the monolayer surface. The IgG sensor showed a linear range from 10 M to 10 M.
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http://dx.doi.org/10.1016/j.foodchem.2020.127881DOI Listing
March 2021

Fabrication of GdO Nanosheet-Modified Glassy Carbon Electrode for Nonenzymatic Highly Selective Electrochemical Detection of Vitamin B2.

ACS Omega 2020 Jul 15;5(29):17892-17899. Epub 2020 Jul 15.

Department of Physics, Alagappa University, Karaikudi 630003, Tamil Nadu, India.

A novel GdO nanosheet was synthesized by the template-free chemical coprecipitation method. Interestingly, upon calcination at 600 °C, nanoparticles were transformed into a nanosheet, as observed from field emission scanning electron microscopy (FESEM) images. An increase in the calcination temperature to 600 °C increases the particle size to 50 nm, which results in aggregation. A sheetlike GdO exhibits superparamagnetism from 300 K. The highly selective nonenzymatic sensing of riboflavin (RF) was studied using a modified glassy carbon electrode with GdO nanosheets, and its various applications were made possible by cyclic voltammetry (CV) and differential pulse voltammetry (DPV). The redox behavior of the RF was determined. The newly fabricated sensor showed high sensitivity, stability, and reproducibility and was also tested with a commercial vitamin B2 tablet and a milk powder sample.
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http://dx.doi.org/10.1021/acsomega.9b04284DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7391253PMC
July 2020

Carbon dots stabilized silver-lipid nano hybrids for sensitive label free DNA detection.

Biosens Bioelectron 2019 May 15;133:48-54. Epub 2019 Mar 15.

Molecular Electronics Laboratory, Department of Bioelectronics and Biosensors, Science Campus, Alagappa University, Karaikudi 630003, India. Electronic address:

Carbon dots have been extensively used for the development of fluorescent based molecular affinity sensors. However, label free DNA sensing by electrochemical method is not reported so far. Herein, we report carbon dots stabilized silver nanoparticles (CD-AgNPs) lipid nano hybrids as a sensitive and selective platform for label free electrochemical DNA sensing. The CD-AgNPs were synthesized by wet chemical method and then characterized by UV-visible, Fourier-transform Infra-red (FT-IR), dynamic light scattering (DLS) and high resolution transmission electron microscopy (HR-TEM) techniques. These CD-AgNPs were used for decorating the binary lipid 1,2-dioleoyl-sn-glycero-3-phosphoethanolamine (DOPE) and N-[1-(2,3-Dioleoyloxy)propyl]-N,N,N-trimethylammonium chloride (DOTAP) surface (named as lipid) and tethered on self-assembled monolayer of 3-mercaptopropionic acid (MPA) (MPA-lipid-CD-AgNPs). The formation of array of MPA-lipid-CD-AgNPs on Au electrode was confirmed by atomic force microscopy (AFM). Electrochemical behavior of MPA- lipid-CD-AgNPs was monitored in the presence of 1 mM potassium ferri/ferrocyanide (K/K [Fe(CN)]). The formation of layer-by-layer MPA-lipid-CD-AgNPs is indicated by increased anodic and cathodic peak (ΔE) separation with decreased redox peak current of K/K [Fe(CN)]. Short chain DNA (30 mer oligonucleotide, representing the lung cancer) was used as a model system for label free DNA sensing. Un-hybridized (single stranded DNA), hybridized (complementary hybridized), single, double and triple base mismatched target DNA hybridized surfaces were efficiently discriminated at 1 µM target DNA concentration at the Au/MPA-lipid-CD-AgNPs electrode by change in the charge transfer resistance from impedance technique. Further, the modified electrode was successfully used to determine target DNA in a wide linear range from 10 to 10 M. The present work open doors for the utilization of CDs in molecular affinity based electrochemical sensor design and development.
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http://dx.doi.org/10.1016/j.bios.2019.03.027DOI Listing
May 2019

Layer-by-layer assembled gold nanoparticles/lower-generation (Gn≤3) polyamidoamine dendrimers-grafted reduced graphene oxide nanohybrids with 3D fractal architecture for fast, ultra-trace, and label-free electrochemical gene nanobiosensors.

Biosens Bioelectron 2018 Nov 16;120:55-63. Epub 2018 Aug 16.

Institute of Functional Materials and Agricultural Applied Chemistry, Jiangxi Agricultural University, Nanchang 330045, PR China. Electronic address:

Three layer-by-layer (LBL) assembled gold nanoparticles (AuNPs)/lower-generation (Gn≤3) polyamidoamine dendrimer (PD) with reduced graphene oxide (rGO) as the core/mercaptopropinoic acid (MPA)/Au were successfully fabricated and employed as electrochemical gene nanobiosensing platforms with three-dimensional (3D) fractal nanoarchitecture for fast, ultra-trace determination of label-free DNA hybridization. Three Gn≤3PD were initially grafted to graphite oxide (GO) via the covalent functionalization between amino terminals of PD and carboxyl terminals of GO where a concomitant reduction of GO, which were covalently linked onto MPA that was self-assembled onto Au substrate, and finally AuNPs were encapsulated onto GG1PD by strong physicochemical interaction between AuNPs and -OH of rGO in GG1PD, Their morphologies, structures, electrochemical properties, and gene nanobiosensing performances were characterized and evaluated. AuNPs/GG2PD-based probe displayed the best excellent structural stability, lowest mobility on solid surface with the increasing charge resistance, widest linear range (1.1 × 10 - 1 × 10), and the lowest limit of detection (1.87 × 10 M) in comparison with both AuNPs/GG1PD-based and AuNPs/GG3PD-based probes. This work will provide a new candidate for the development of metal nanoparticles functionalized PD with inorganic nonmetallic nanomaterials as cores with 3D fractal nanoarchitecture and promising electrochemical gene nanobiosensing platforms based on dendrimer-nanoinorganic hybrids with 3D nanoarchitectures and LBL assembly for fast and ultra-trace detection of label-free DNA hybridization with potential application in bioanalysis and medical diagnosis of genetic diseases.
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http://dx.doi.org/10.1016/j.bios.2018.08.032DOI Listing
November 2018

Layer-by-Layer-Assembled AuNPs-Decorated First-Generation Poly(amidoamine) Dendrimer with Reduced Graphene Oxide Core as Highly Sensitive Biosensing Platform with Controllable 3D Nanoarchitecture for Rapid Voltammetric Analysis of Ultratrace DNA Hybridization.

ACS Appl Mater Interfaces 2018 Jun 12;10(25):21541-21555. Epub 2018 Jun 12.

Institute of Functional Materials and Agricultural Applied Chemistry , Jiangxi Agricultural University , Nanchang 330045 , P. R. China.

The structure and electrochemical properties of layer-by-layer-assembled gold nanoparticles (AuNPs)-decorated first-generation (G1) poly(amidoamine) dendrimer (PD) with reduced graphene oxide (rGO) core as a highly sensitive and label-free biosensing platform with a controllable three-dimensional (3D) nanoarchitecture for the rapid voltammetric analysis of DNA hybridization at ultratrace levels were characterized. Mercaptopropinoic acid (MPA) was self-assembled onto Au substrate, then GG1PD formed by the covalent functionalization between the amino terminals of G1PD and carboxyl terminals of rGO was covalently linked onto MPA, and finally AuNPs were decorated onto GG1PD by strong physicochemical interaction between AuNPs and -OH of rGO in GG1PD, which was characterized through different techniques and confirmed by computational calculation. This 3D controllable thin-film electrode was optimized and evaluated using [Fe(CN)] as the redox probe and employed to covalently immobilize thiol-functionalized single-stranded DNA as biorecognition element to form the DNA nanobiosensor, which achieved fast, ultrasensitive, and high-selective differential pulse voltammetric analysis of DNA hybridization in a linear range from 1 × 10 to 1 × 10 g m with a low detection limit of 9.07 × 10 g m. This work will open a new pathway for the controllable 3D nanoarchitecture of the layer-by-layer-assembled metal nanoparticles-functionalized lower-generation PD with two-dimensional layered nanomaterials as cores that can be employed as ultrasensitive and label-free nanobiodevices for the fast diagnosis of specific genome diseases in the field of biomedicine.
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http://dx.doi.org/10.1021/acsami.8b03236DOI Listing
June 2018

Correction: One-step coelectrodeposition-assisted layer-by-layer assembly of gold nanoparticles and reduced graphene oxide and its self-healing three-dimensional nanohybrid for an ultrasensitive DNA sensor.

Nanoscale 2018 02;10(5):2658

Department of Bioelectronics and Biosensors, Alagappa University, Karaikudi-630003, India.

Correction for 'One-step coelectrodeposition-assisted layer-by-layer assembly of gold nanoparticles and reduced graphene oxide and its self-healing three-dimensional nanohybrid for an ultrasensitive DNA sensor' by Jayakumar Kumarasamy, et al., Nanoscale, 2018, DOI: 10.1039/c7nr06952a.
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http://dx.doi.org/10.1039/c8nr90011fDOI Listing
February 2018

Synthesis and characterisation of arsenic nanoparticles and its interaction with DNA and cytotoxic potential on breast cancer cells.

Chem Biol Interact 2018 Nov 22;295:73-83. Epub 2017 Dec 22.

Department of Biochemistry and Molecular Biology, Pondicherry University, Puducherry 605 014, India. Electronic address:

Therapeutic applications of arsenic trioxide (ATO) are limited due to their severe adverse effects. However, nanoparticles of ATO might possess inimitable biologic effects based on their structure and size which differ from their parent molecules. Based on this conception, AsNPs were synthesized from ATO and comparatively analysed for their interaction mechanism with DNA using spectroscopic & electrochemical techniques. Finally, anti-proliferative activity was assessed against different breast cancer cells (MDA-MB-231 & MCF-7) and normal non-cancerous cells (HEK-293). The DNA interaction study revealed that AsNPs and ATO exhibit binding constant values in the order of 10 which indicates strong binding interaction. Binding of AsNPs did not disturb the structural integrity of DNA, on the other hand an opposing effect was observed with ATO through biophysical techniques. Further, in vitro study, confirms cytotoxicity of ATO and AsNPs against different cells, however at particular concentration ATO exhibits more cytotoxicity than that of AsNPs. Furthermore, cytotoxicity was confirmed through acridine orange and comet assay. In conclusion, AsNPs are safer than ATO with comparable efficacy and might be a suitable candidate for the development of novel therapeutic agent against breast cancer and other solid tumours.
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http://dx.doi.org/10.1016/j.cbi.2017.12.025DOI Listing
November 2018

One-step coelectrodeposition-assisted layer-by-layer assembly of gold nanoparticles and reduced graphene oxide and its self-healing three-dimensional nanohybrid for an ultrasensitive DNA sensor.

Nanoscale 2018 01;10(3):1196-1206

Department of Bioelectronics and Biosensors, Alagappa University, Karaikudi-630003, India.

A layer-by-layer (LBL) assembly was employed for preparing multilayer thin films with a controlled architecture and composition. In this study, we report the one-step coelectrodeposition-assisted LBL assembly of both gold nanoparticles (AuNPs) and reduced graphene oxide (rGO) on the surface of a glassy carbon electrode (GCE) for the ultrasensitive electrochemical impedance sensing of DNA hybridization. A self-healable nanohybrid thin film with a three-dimensional (3D) alternate-layered nanoarchitecture was obtained by the one-step simultaneous electro-reduction of both graphene oxide and gold chloride in a high acidic medium of HSO using cyclic voltammetry and was confirmed by different characterization techniques. The DNA bioelectrode was prepared by immobilizing the capture DNA onto the surface of the as-obtained self-healable AuNP/rGO/AuNP/GCE with a 3D LBL nanoarchitecture via gold-thiol interactions, which then served as an impedance sensing platform for the label-free ultrasensitive electrochemical detection of DNA hybridization over a wide range from 1.0 × 10 to 1.0 × 10 g ml, a low limit of detection of 3.9 × 10 g ml (S/N = 3), ultrahigh sensitivity, and excellent selectivity. This study presents a promising electrochemical sensing platform for the label-free ultrasensitive detection of DNA hybridization with potential application in cancer diagnostics and the preparation of a self-healable nanohybrid thin film with a 3D alternate-layered nanoarchitecture via a one-step coelectrodeposition-assisted LBL assembly.
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http://dx.doi.org/10.1039/c7nr06952aDOI Listing
January 2018

Supported binary liposome vesicle-gold nanoparticle for enhanced label free DNA and protein sensing.

Biosens Bioelectron 2017 Sep 20;95:168-173. Epub 2017 Apr 20.

Molecular Electronics Laboratory, Department of Bioelectronics and Biosensors, Science Campus, Alagappa University, Karaikudi 630003, India. Electronic address:

Supported binary liposome mixture of cationic liposome N-[1-(2,3-Dioleoyloxy)propyl]-N,N,N-trimethylammonium propane (DOTAP) and the zwitterionic liposome 1,2-Dioleoyl-sn-Glycero-3-Phosphoethanolamine (DOPE) were tethered on thiol monolayers in the absence and presence of gold nanoparticle to enhance sensor stability and sensitivity for label free DNA and protein sensing for the first time. Cysteamine hydrochloride (Cyst), 3-Mercaptopropionic acid (MPA), 11-Mercaptoundecanoic acid (MUDA) and 11-amino-1-undecane thiol (AUT) monolayers were used as tethers on gold surfaces. Electrochemical studies in the presence of [Fe(CN)] indicate that the presence of both DOPE and AuNP decreases the electrostatic interaction between DOTAP and MPA layer during the formation of DOPE-DOTAP-AuNP (DDA) whereas they enhance the repulsive force on the Cyst and AUT monolayers. In the thiol monolayer supported DDA, the gelation of neutral lipid DOPE by the AuNP is disfavored which inturn promotes stability of vesicle structure. The membrane protein melittin's interaction with the DDA indicates the presence of intact vesicle by showing decreased charge transfer for the MUDA and AUT in the presence of [Fe(CN)]. On the contrary, the presence of the bilayer and semi circled DDA on the MPA and cysteamine layers were confirmed by the increased redox reaction. Atomic Force Microscopic (AFM) and Transmission Electron Microscopic (TEM) images support the presence of an array like semi circled DDA on the MPA and well separated DDA vesicles on the MUDA with variable sizes. Dynamic Light Scattering (DLS) and Fourier Transform Infrared spectroscopy (FTIR) suggest effective coordination between DOPE, DOTAP and AuNP. Label free DNA hybridization sensing in presence of the negatively charged [Fe(CN)] indicates the lowest DNA detection limit of 1×10M with linearity range 1×10 to 1×10M. Similarly, streptavidin sensing shows the lowest detection of 1ngml with a linear range 100ng to 1µg due to the increased reactive sites and distance.
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http://dx.doi.org/10.1016/j.bios.2017.04.022DOI Listing
September 2017

Construction of spherical liposome on solid transducers for electrochemical DNA sensing and transfection.

Appl Biochem Biotechnol 2014 Oct 6;174(3):1137-50. Epub 2014 Jun 6.

Molecular Electronics Laboratory, Department of Bioelectronics and Biosensors, Alagappa University, Karaikudi, 630 003, India.

Cationic 1,2-dioleoyl trimethyl ammonium propane (DOTAP) and neutral 1,2-dioleoyl-sn-glycero-3-phosphoethanolamine (DOPE) are anchored on cysteamine (cyst), mercaptopropionic acid (MPA) monolayer (thiol monolayers) modified on an individual gold transducer. DOTAP and DOPE are mixed with gold nanoparticle (AuNP) to form spherical liposome-AuNP. The electrochemical behaviors of the surface attached DOTAP-AuNP and DOPE-AuNP in presence of [Fe(CN)6](3-/4-) depend on the method of layer formation. Transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FTIR), atomic force microscopy (AFM), and ultraviolet (UV)-visible spectroscopic techniques are used to characterize the liposome-AuNP nanocomposite. The studies indicate stability of spherical liposome-AuNP on the gold transducer. Label-free DNA hybridization detection on these surfaces reveals different detection limits. Confocal laser scanning microscopy (CLSM) is used to confirm the cell transfection.
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http://dx.doi.org/10.1007/s12010-014-0992-1DOI Listing
October 2014

Sandwiching spherical 1,2-dioleoyltrimethylammoniumpropane liposome in gold nanoparticle on solid transducer for electrochemical ultrasensitive DNA detection and transfection.

Biosens Bioelectron 2014 Aug 2;58:326-32. Epub 2014 Mar 2.

Molecular Electronics Laboratory, Department of Bioelectronics and Biosensors, Alagappa University, Karaikudi 630003, India. Electronic address:

Cationic N-[1-(2,3-Dioleoyloxy)propyl]-N,N,N-trimethylammonium propane (DOTAP) liposome is spherically sandwiched in gold nanoparticle (abbreviated as sDOTAP-AuNP) onto a gold electrode surface. The sDOTAP-AuNP is applied for electrochemical label free DNA sensing and Escherichia coli cell transfection for the first time. Complementary target (named as hybridized), non-complementary target (un-hybridized) and single base mismatch target (named as SMM) hybridized surfaces are discriminated sensitively and selectively in presence of [Fe(CN)6](3-/4-). Double strand specific intercalator methylene blue in combination with [Fe(CN)6](3-) is used to enhance target detection limit down to femtomolar concentration. Cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), differential pulse voltammetry (DPV) techniques are used for characterizing DNA sensing. High Resolution Transmission Electron Microscopy (HRTEM), Fourier Transform Infrared Spectroscopy (FTIR), Atomic Force Microscopy (AFM) and Dynamic Light Scattering (DLS) techniques are used to confirm the spherical nature of the sDOTAP-AuNP-DNA composite in solution and on the solid surface. DNA on the sDOTAP-ssDNA is transferred by potential stripping method (+0.2V (Ag/AgCl)) into buffer solution containing E. coli cells. The transfection is confirmed by the contrast images for the transfected and non-transfected cell from Confocal Laser Scanning Microscopy (CLSM). The results demonstrate effectiveness of the electrochemical DNA transfection method developed and could be applied for other cells.
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http://dx.doi.org/10.1016/j.bios.2014.02.033DOI Listing
August 2014

Tethering of spherical DOTAP liposome gold nanoparticles on cysteamine monolayer for sensitive label free electrochemical detection of DNA and transfection.

Analyst 2014 May;139(10):2467-75

Molecular Electronics Laboratory, Department of Bioelectronics and Biosensors, Science Block, Alagappa University, Karaikudi, 630 004, India.

Construction of spherical liposomes is critical for developing tools for targeted gene and drug delivery applications in biotechnology and medicine, however, it has been demonstrated only in solution phase until now. Spherical liposome tethering on pristine thiol monolayer on gold transducer and its application to label free DNA sensing and transfection has rarely been reported. Here, we report tethering of spherical 1,2-dioleoyltrimethylammoniumpropane liposome-gold nanoparticle (DOTAP-AuNP) on amine terminated monolayer by simple electrostatic interaction on gold transducer for the first time. Cuddling of cationic liposome by AuNP prevents spherical vesicle fusion in both liquid and solid phases, an essential criterion required for gene and drug delivery applications. The spherical nature of DOTAP-AuNPs on a gold surface is confirmed electrochemically using both [Fe(CN)6](3-/4-) and [Ru(NH3)6](3+) redox probes. Atomic force microscopy (AFM), Fourier transform infrared spectroscopy (FTIR), transmission electron microscopy (TEM), dynamic light scattering (DLS) and ultraviolet-visible (UV) spectroscopic techniques confirm the robust nature of spherical liposome-AuNPs on solid and in liquid phases. The surface is applied for label free DNA hybridization and single nucleotide polymorphism detections sensitively and selectively without signal amplification. The lowest target DNA concentration detected is 100 attomole. DNA transfection is made simply by dropping E. coli cells on DOTAP-AuNP-DNA immobilized transducer surface. The difference between the fluorescent image of transfected E. coli and the differential interference contrast image of E. coli cells by confocal laser scanning microscopy (CLSM) confirms the efficiency and simplicity of the transfection method developed in terms of reduced cost and reagents.
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http://dx.doi.org/10.1039/c4an00017jDOI Listing
May 2014

Graphene-PAMAM dendrimer-gold nanoparticle composite for electrochemical DNA hybridization detection.

Methods Mol Biol 2013 ;1039:201-19

Molecular Electronics Lab, Department of Bioelectronics and Biosensors, Alagappa University, Karaikudi, India.

Graphene oxide is chemically functionalized using planar structured first generation polyamidoamine dendrimer (G1PAMAM) to form graphene core GG1PAMAM. The monolayer of GG1PAMAM is anchored on the 3-mercapto propionic acid monolayer pre-immobilized onto a gold transducer. The GG1PAMAM is decorated using gold nanoparticles for the covalent attachment of single-stranded DNA through simple gold-thiol chemistry. The single- and double-stranded DNAs are discriminated electrochemically in the presence of redox probe K3[Fe(CN)6]. Double-stranded-specific intercalator methylene blue is used to enhance the lower detection limit. The use of linear and planar G1PAMAM along with the graphene core has enhanced the detection limit 100 times higher than the G1PAMAM with the conventional ethylene core. This chapter presents the details of GG1PAMAM preparation and application to DNA sensing by electrochemical methods.
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http://dx.doi.org/10.1007/978-1-62703-535-4_17DOI Listing
March 2014