Publications by authors named "Mian Hasnain Nawaz"

17 Publications

  • Page 1 of 1

MIP-Based Impedimetric Sensor for Detecting Dengue Fever Biomarker.

Appl Biochem Biotechnol 2020 Aug 26;191(4):1384-1394. Epub 2020 Feb 26.

Interdisciplinary Research Centre in Biomedical Materials (IRCBM), COMSATS University Islamabad, Lahore Campus, Lahore, 54600, Pakistan.

In this study, molecular imprinted polymer (MIP)-based impedimetric sensor has been developed to detect dengue infection at an early stage. Screen-printed carbon electrode (SPCE) was modified with electrospun nanofibers of polysulfone (PS) and then, coated with dopamine while using NS1 (non-structural protein 1-a specific and sensitive biomarker for dengue virus infection) as template during polymerization. The self-polymerization of dopamine at room temperature helps to retain exact structure of template (NS1) which results in generating geometrically fit imprinted sites for specific detection of target analyte. The electrochemical properties of MIP-modified SPCEs were studied by cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) at every step of modification. Under optimal conditions, impedimetric measurements showed linear response in the range from 1 to 200 ng/mL. The developed sensor can selectively detect NS1 concentrations as low as 0.3 ng/mL. Moreover, impedimetric sensor system was also employed for NS1 determination in real human serum samples and satisfying recoveries varying from 95 to 97.14% were obtained with standard deviations of less than 5%.
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http://dx.doi.org/10.1007/s12010-020-03285-yDOI Listing
August 2020

Nitrogen-doped graphene oxide as a catalyst for the oxidation of Rhodamine B by hydrogen peroxide: application to a sensitive fluorometric assay for hydrogen peroxide.

Mikrochim Acta 2019 12 16;187(1):47. Epub 2019 Dec 16.

Interdisciplinary Research Centre in Biomedical Materials (IRCBM), COMSATS University Islamabad, Lahore Campus, Lahore, Punjab, 54000, Pakistan.

The authors report that nitrogen-doped graphene oxide (NGO) catalyzes the oxidative decomposition of the fluorophore Rhodamine B (RhB) by hydrogen peroxide. The catalytic decomposition of hydrogen peroxide yields free hydroxyl radicals that destroy RhB so that the intensity of the yellow fluorescence is reduced. Nitrogen doping enhances the electronic and optical properties and surface chemical reactivities of GO such as widening of bandgap, increase in conductivity, enhanced quenching and adsorbing capabilities etc. The catalytic properties of NGO are attributed to its large specific surface and high electron affinity of nitrogen atoms. The chemical and structural properties of GO and NGO were characterized by XRD, FTIR, SEM, UV-visible and Raman spectroscopies. The method was optimized by varying the concentration of RhB, nitrogen dopant and hydrogen peroxide. The fluorescent probe, best operated at excitation/emission wavelengths of 554/577 nm, allows hydrogen peroxide to be determined in concentrations as low as 94 pM with a linear range spanning from 1 nM to 1 μM. Graphical abstract Schematic illustration of a fluorescence quenching method for the determination of HO. Upon addition of HO, nitrogen-doped graphene oxide (NGO) catalyzes the oxidation of Rhodamine B dye due to hydroxyl radical generation, which leads to a sensitive quenchometric methd for H O.
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http://dx.doi.org/10.1007/s00604-019-3994-4DOI Listing
December 2019

N-Doped Graphene Oxide Decorated with PtCo Nanoparticles for Immobilization of Double-Stranded Deoxyribonucleic Acid and Investigation of Clenbuterol-Induced DNA Damage.

ACS Omega 2019 Oct 26;4(15):16524-16530. Epub 2019 Sep 26.

Center for Advanced Analytical Science, c/o School of Chemistry and Chemical Engineering, Guangzhou University, Guangzhou 510006, P.R. China.

We demonstrate here a facile hydrothermal-assisted formation of PtCo alloy nanoparticles (NPs) and their simultaneous anchoring on the graphitic surface of N-doped graphene oxide (NGO). Doping induced nanopores in the carbon surface to facilitate the uniform and homogeneous anchoring of alloy nanoparticles. It was revealed that the formation of PtCo NPs on an NGO interface plodded excellent tendency toward double-stranded deoxyribonucleic acid (dsDNA). The dsDNA immobilization was enabled by the presence of several oxidation states of Pt and Co. The same property was further used to monitor the direct detection of dsDNA damage induced by clenbuterol via screen-printed carbon electrodes. Cyclic voltammetric and electrochemical impedance spectroscopic characterization traced well the dsDNA attachment on the modified electrode surface. Differential pulsed voltammetry was further used as a tool to monitor the characteristic guanine peak before and after incubating with clenbuterol used as a damage probe for the dsDNA. The findings can further be appurtenant in exploring dsDNA immobilization protocols and developing analytical methods for determination of various dsDNA damaging agents.
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http://dx.doi.org/10.1021/acsomega.9b02184DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6788047PMC
October 2019

Construction of sponge-like graphitic carbon nitride and silver oxide nanocomposite probe for highly sensitive and selective turn-off fluorometric detection of hydrogen peroxide.

J Colloid Interface Sci 2020 Jan 28;558:230-241. Epub 2019 Sep 28.

Interdisciplinary Research Centre in Biomedical Materials (IRCBM), COMSATS University Islamabad, Lahore Campus, 1.5 Km Defence Road, Off Raiwind Road, Lahore, Punjab 54000, Pakistan. Electronic address:

In the present work, spongy graphitic carbon nitride (GCN) and silver oxide nanocomposites were prepared through a facile hydrothermal method at 160 °C for 4 h using GCN, silver nitrate, and dipotassium hydrogen phosphate as the starting materials. The prepared samples were characterized by scanning electron microscopy, energy dispersive X-ray spectrometry, Brunauer-Emmett-Teller method, X-ray diffraction, X-ray photoelectron spectroscopy (XPS), UV-Visible diffuse reflectance spectroscopy, Fourier transform infrared spectroscopy, Raman, and photoluminescence techniques. SEM images showed AgO loaded GCN nanocomposite has a sponge-like structure due to the interconnecting of the enormous layer on the planar structure of GCN. XRD of samples showed the diffraction planes due to the hexagonal structure of carbon nitride with a decrease in intensity of peaks with increasing silver oxide (AgO) in the nanocomposite. Further, the addition of silver oxide improved the electrical properties of the nanocomposite by reducing the recombination of electron and hole pairs as shown by photoluminescence spectra. XPS spectra have confirmed the oxidation state of Ag as well as the coexistence of AgO and GCN in the nanocomposite. BET results indicated the increase in surface area for AgO/GCN-4.2% nanocomposite as compared to GCN. FTIR study indicated that the graphitic structure in GCN remained intact with the loading of AgO. A fluorescent quenching based HO sensor was constructed by simultaneous oxidation of Rhodamine B in the presence of hydrogen peroxide and nanocomposite as the catalyst. In phosphate buffer saline at room temperature, Rhodamine B displayed a strong fluorescence emission peak around 577 nm under an excitation wavelength of 554 nm. This fluorescence signal of Rhodamine B was quenched in the presence of HO and nanocomposite. The catalytic fluorescence quenching was increased with the increase in HO concentration in the reaction system. The detection conditions of the prepared sensor were optimized as a reaction temperature of 25 °C, Rhodamine B concentration as 66 ng mL and nanocomposite concentration as 56 µg mL. The catalytic fluorescence quenching response of the biosensor exhibited a linear range and limit of detection for HO as 30-300 nM and 22 nM respectively.
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http://dx.doi.org/10.1016/j.jcis.2019.09.109DOI Listing
January 2020

MoS/ZnO-Heterostructures-Based Label-Free, Visible-Light-Excited Photoelectrochemical Sensor for Sensitive and Selective Determination of Synthetic Antioxidant Propyl Gallate.

Anal Chem 2019 08 27;91(16):10657-10662. Epub 2019 Jun 27.

State Key Laboratory of Electroanalytical Chemistry, c/o Engineering Laboratory for Modern Analytical Techniques, Changchun Institute of Applied Chemistry , Chinese Academy of Sciences , Changchun 130022 , China.

Propyl gallate (PG) as one of the important synthetic antioxidants is widely used in the prevention of oxidative deterioration of oils during processing and storage. Determination of PG has received extensive concern because of its possible toxic effects on human health. Herein, we report a photoelectrochemical (PEC) sensor based on ZnO nanorods and MoS flakes with a vertically constructed p-n heterojunction. In this system, the n-type ZnO and p-type MoS heterostructures exhibited much better optoelectronic behaviors than their individual materials. Under an open circuit potential (zero potential) and visible light excitation (470 nm), the PEC sensor exhibited extraordinary response for PG determination, as well as excellent anti-inference properties and good reproducibility. The PEC sensor showed a wide linear range from 1.25 × 10 to 1.47 × 10 mol L with a detection limit as low as 1.2 × 10 mol L. MoS/ZnO heterostructure with proper band level between MoS and ZnO could make the photogenerated electrons and holes separated more easily, which eventually results in great improvement of sensitivity. On the other hand, formation of a five membered chelating ring structure of Zn(II) with adjacent oxygen atoms of PG played significant roles for selective detection of PG. Moreover, the PEC sensor was successfully used for PG analysis in different samples of edible oils. It demonstrated the ability and reliability of the MoS/ZnO-based PEC sensor for PG detection in real samples, which is beneficial for food quality monitoring and reducing the risk of overuse of PG in foods.
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http://dx.doi.org/10.1021/acs.analchem.9b01889DOI Listing
August 2019

A nanocomposite prepared from magnetite nanoparticles, polyaniline and carboxy-modified graphene oxide for non-enzymatic sensing of glucose.

Mikrochim Acta 2019 04 2;186(5):267. Epub 2019 Apr 2.

Interdisciplinary Research Centre in Biomedical Materials (IRCBM), COMSATS University Islamabad Lahore Campus, Lahore, 55150, Pakistan.

The authors report on the synthesis of carboxy functionalized graphene oxide (fGO) decorated with magnetite (FeO) nanoparticles. The resulting nanomaterial was used to prepare a composite with polyaniline (PANI) which was characterized by UV-vis, Fourier transform-infrared and Raman spectroscopies. Its surface morphologies were characterized by atomic force and scanning electron microscopies. A screen-printed carbon electrode was then modified with the nanocomposite to obtain an enzyme-free glucose sensor. The large surface of fGO and FeO along with the enhanced charge transfer capability of PANI warrant a pronounced electrochemical response (typically measured at 0.18 V versus Ag/AgCl) which is suppressed in the presence of glucose. This reduction of current by glucose was used to design a sensitive method for quantification of glucose. The response of the modified SPCE is linear in the 0.05 μM - 5 mM glucose concentration range, and the lower detection limit is 0.01 μM. Graphical abstract Schematic illustration of in-situ anchoring of Iron oxide on functionalized graphene oxide and synthesis of its polymeric nanocomposite for non-enzymatic detection of Glucose. The nanocomposite modified screen printed interface enabled monitoring of glucose at lower potential with higher precision. GO (graphene oxide), fGO (functionalized graphene oxide), PANI (polyaniline).
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http://dx.doi.org/10.1007/s00604-019-3364-2DOI Listing
April 2019

A Review of the Construction of Nano-Hybrids for Electrochemical Biosensing of Glucose.

Biosensors (Basel) 2019 Mar 25;9(1). Epub 2019 Mar 25.

BAE: Biocapteurs-Analyses-Environnement, Universite de Perpignan ViaDomitia, 52 Avenue Paul Alduy, 66860 Perpignan CEDEX, France.

Continuous progress in the domain of nano and material science has led to modulation of the properties of nanomaterials in a controlled and desired fashion. In this sense, nanomaterials, including carbon-based materials, metals and metal oxides, and composite/hybrid materials have attracted extensive interest with regard to the construction of electrochemical biosensors. The modification of a working electrode with a combination of two or three nanomaterials in the form of nano-composite/nano-hybrids has revealed good results with very good reproducibility, stability, and improved sensitivity. This review paper is focused on discussing the possible constructs of nano-hybrids and their subsequent use in the construction of electrochemical glucose biosensors.
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http://dx.doi.org/10.3390/bios9010046DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6468850PMC
March 2019

CoO nanostructures on flexible carbon cloth for crystal plane effect of nonenzymatic electrocatalysis for glucose.

Biosens Bioelectron 2019 Jan 18;123:25-29. Epub 2018 Jul 18.

State Key Laboratory of Electroanalytical Chemistry, c/o Engineering Laboratory for Modern Analytical Techniques, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022, PR China; Center for Advanced Analytical Science, c/o School of Chemistry and Chemical Engineering, Guangzhou University, Guangzhou 510006, PR China. Electronic address:

This work accounts the influence of facet effect of CoO nanocrystals towards nonenzymatic electrocatalysis of glucose induced by different crystal planes modified on carbon cloth (CC) electrode. Tuning the molar ratio of precursor compounds during hydrothermal synthesis of CoO, followed by thermal decomposition protocols, different crystal structure including nanocubes, nanothorns, nanooctahedrons and nanosheets were obtained with respective {001}, {110}, {111} and {112} facets. The electrochemical results of these different CoO crystals demonstrate that the nanooctahedron with crystal plane of {111} displays the best nonenzymatic electro-catalytic glucose activity with widest linear range (0.5-1000 μM), highest sensitivity (246.8 μA mM) and detection limit of 0.012 μM (S/N = 3). Interestingly, the electrocatalytic activity for nonenzymatic electro-catalytic glucose is ranked in the order of {111} > {112} > {110} > {001}.
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http://dx.doi.org/10.1016/j.bios.2018.07.039DOI Listing
January 2019

Development of a portable and disposable NS1 based electrochemical immunosensor for early diagnosis of dengue virus.

Anal Chim Acta 2018 Oct 18;1026:1-7. Epub 2018 Apr 18.

BAE: Biocapteurs-Analyses-Environment, Universite de Perpignan Via Domitia, 52 Avenue Paul Alduy, Perpignan Cedex, 66860, France. Electronic address:

The present study represents fabrication of nonstructural antibody (NS1) based immunosensor coupled with bovine serum albumin (BSA) modified screen printed carbon electrodes (SPCE) as transducing substrate for the early diagnosis of dengue virus. The anti-NS1 monoclonal antibody was immobilized on electro grafted BSA surface of working electrode. The electrons transfer resistance before and after NS1 attachment was monitored as a function of its concentration to perform the qualitative and quantitative analysis. The as prepared impedimetric immunosensor successfully detected the dengue virus protein with enhanced limit of detection (0.3 ng/mL) and linear range (1-200 ng/mL). The selectivity of the designed device was further elaborated with several interfering analytes and was finally demonstrated with human serum samples. The extravagant selectivity, sensitivity and easier fabrication protocol corroborate the potential applications of such immunosensor for practical diagnosis of dengue virus.
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http://dx.doi.org/10.1016/j.aca.2018.04.032DOI Listing
October 2018

Ionic liquid coated iron nanoparticles are promising peroxidase mimics for optical determination of HO.

Mikrochim Acta 2018 05 16;185(6):302. Epub 2018 May 16.

Interdisciplinary Research Centre in Biomedical Materials (IRCBM) COMSATS Institute of Information Technology, Lahore, 54000, Pakistan.

Ionic liquid coated nanoparticles (IL-NPs) consisting of zero-valent iron are shown to display intrinsic peroxidase-like activity with enhanced potential to catalyze the oxidation of the chromogenic substrate 3,3',5,5'-tetramethylbenzidine (TMB) in the presence of hydrogen peroxide. This results in the formation of a blue green colored product that can be detected with bare eyes and quantified by photometry at 652 nm. The IL-NPs were further doped with bismuth to enhance its catalytic properties. The Bi-doped IL-NPs were characterized by FTIR, X-ray diffraction and scanning electron microscopy. A colorimetric assay was worked out for hydrogen peroxide that is simple, sensitive and selective. Response is linear in the 30-300 μM HO concentration range, and the detection limit is 0.15 μM. Graphical abstract Schematic of ionic liquid coated iron nanoparticles that display intrinsic peroxidase-like activity. They are capable of oxidizing the chromogenic substrate 3,3',5,5'-tetramethylbenzidine (TMB) in the presence of hydrogen peroxide. This catalytic oxidation generated blue-green color can be measured by colorimetry. Response is linear in the range of 30-300 μM HO concentration, and the detection limit is 0.15 μM.
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http://dx.doi.org/10.1007/s00604-018-2841-3DOI Listing
May 2018

Biomimetic nitrogen doped titania nanoparticles as a colorimetric platform for hydrogen peroxide detection.

J Colloid Interface Sci 2017 Nov 6;505:1147-1157. Epub 2017 Jul 6.

Interdisciplinary Research Centre in Biomedical Materials (IRCBM), COMSATS Institute of Information Technology, Lahore 54000, Pakistan. Electronic address:

Nanoparticles proved a viable alternative to the already used sensing and diagnostics methods due to their low cost, good stability, easy availability and easy synthesis. In the present approach, nitrogen doped titania nanoparticles are prepared through freeze drying method, and subsequently stabilized through ionic liquid. These nanoparticles were characterized through various techniques such as X-ray diffraction (XRD), Fourier transformation infrared spectroscopy (FTIR), Scanning electron microscopy (SEM), BET pore size and surface area analyzer, X-ray photoelectron spectroscopy (XPS) and UV-Visible diffuse reflectance spectroscopy (UV-Vis. DRS). The synthesized nitrogen doped titania nanoparticles were proved to be a novel peroxidase mimetic with great potential to catalyze oxidation of 3,3',5,5'-tetramethylbenzidine (TMB) in the presence of hydrogen peroxide (HO) to form a blue color product. As a proof of concept, this new enzyme mimic was used as a robust nanoprobe for the detection of hydrogen peroxide with improved analytical characteristics. A linear response for hydrogen peroxide detection was obtained in the range of 10-300μmol/L, with a detection limit of 2.5μmol/L. Taking into account the valuable intrinsic peroxidase activity, the present work may find widespread applications in the field of sensors and biosensors for diverse applications.
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http://dx.doi.org/10.1016/j.jcis.2017.07.014DOI Listing
November 2017

One Step Assembly of Thin Films of Carbon Nanotubes on Screen Printed Interface for Electrochemical Aptasensing of Breast Cancer Biomarker.

Sensors (Basel) 2016 Oct 6;16(10). Epub 2016 Oct 6.

Interdisciplinary Research Centre in Biomedical Materials (IRCBM), COMSATS Institute of Information Technology, Lahore 54000, Pakistan.

Thin films of organic moiety functionalized carbon nanotubes (CNTs) from a very well-dispersed aqueous solution were designed on a screen printed transducer surface through a single step directed assembly methodology. Very high density of CNTs was obtained on the screen printed electrode surface, with the formation of a thin and uniform layer on transducer substrate. Functionalized CNTs were characterized by X-ray diffraction spectroscopy (XRD), Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA) and Brunauer-Emmett- Teller (BET) surface area analyzer methodologies, while CNT coated screen printed transducer platform was analyzed by scanning electron microscopy (SEM), atomic force microscopy (AFM), cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). The proposed methodology makes use of a minimum amount of CNTs and toxic solvents, and is successfully demonstrated to form thin films over macroscopic areas of screen printed carbon transducer surface. The CNT coated screen printed transducer surface was integrated in the fabrication of electrochemical aptasensors for breast cancer biomarker analysis. This CNT coated platform can be applied to immobilize enzymes, antibodies and DNA in the construction of biosensor for a broad spectrum of applications.
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http://dx.doi.org/10.3390/s16101651DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5087439PMC
October 2016

Thiol-ubiquinone assisted fragmentation of gold nanoparticles.

Chem Commun (Camb) 2013 Feb;49(17):1738-40

State Key Laboratory of Bioreactor Engineering & Department of Chemistry, East China University of Science and Technology, 130 Meilong Road, Shanghai, 200237, China.

We report the spontaneous fragmentation of gold nanoparticles (AuNPs) induced, in aqueous solution at room temperature, by thiol derivative of ubiquinone, which involves the energetic electron injection from thiol-ubiquinone to the gold nanoparticles.
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http://dx.doi.org/10.1039/c3cc38398aDOI Listing
February 2013

3-Hydr-oxy-N'-[(Z)-(5-methyl-2-fur-yl)methyl-idene]naphthalene-2-carbo-hydrazide.

Acta Crystallogr Sect E Struct Rep Online 2009 Oct 23;65(Pt 11):o2845-6. Epub 2009 Oct 23.

The asymmetric unit of title compound, C(17)H(14)N(2)O(3), contains three independent mol-ecules. In one of these mol-ecules, the 5-methyl-2-furyl group is disordered over two sets of sites with an occupancy ratio of 0.747 (3):0.253 (3). In the two ordered mol-ecules, the furan and naphthalene rings are oriented at dihedral angles of 11.05 (12) and 32.2 (5)°. In the disordered mol-ecule, the furan rings with major and minor occupancies are oriented at dihedral angles of 41.4 (2) and 26.6 (13)°, respectively, with the corresponding naphthalene ring. An intra-molecular O-H⋯O hydrogen bond occurs within each mol-ecule. In the crystal, mol-ecules are linked by N-H⋯O, N-H⋯(N,O) and C-H⋯O inter-actions.
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http://dx.doi.org/10.1107/S1600536809043141DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2971404PMC
October 2009

N'-[(E)-1-(3-Fluoro-phen-yl)ethyl-idene]formohydrazide.

Acta Crystallogr Sect E Struct Rep Online 2009 Oct 23;65(Pt 11):o2830. Epub 2009 Oct 23.

In the title compound, C(9)H(9)FN(2)O, the dihedral angle between the fluoro-benzene ring and the mean plane of the side chain is 15.59 (14)°. In the crystal, the mol-ecules form inversion dimers linked by pairs of N-H⋯O hydrogen bonds, resulting in R(2) (2)(8) loops. These dimers are reinforced by C-H⋯O inter-actions.
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http://dx.doi.org/10.1107/S1600536809042809DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2971114PMC
October 2009

N'-[(E)-(5-Methyl-furan-2-yl)methyl-idene]formohydrazide.

Acta Crystallogr Sect E Struct Rep Online 2009 Sep 19;65(Pt 10):o2495. Epub 2009 Sep 19.

The title compound, C(7)H(8)N(2)O(2), is almost planar (r.m.s. deviation for non-H atoms = 0.029 Å). In the crystal, inversion dimers linked by pairs of N-H⋯O hydrogen bonds generate an R(2) (2)(8) ring motif.
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http://dx.doi.org/10.1107/S1600536809037064DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2970214PMC
September 2009

N'-[(1E)-1-(4-Chloro-phen-yl)ethyl-idene]formohydrazide.

Acta Crystallogr Sect E Struct Rep Online 2009 Sep 19;65(Pt 10):o2494. Epub 2009 Sep 19.

The structure of the title compound, C(9)H(9)ClN(2)O, consists of centrosymmetric dimers due to inter-molecular N-H⋯O hydrogen bonding, forming R(2) (2)(8) ring motifs. The dihedral angle between the p-chloro-phenyl unit and the remaining heavy-atom group is 6.77 (17)°.
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http://dx.doi.org/10.1107/S1600536809037143DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2970209PMC
September 2009