Pub Date : 2019-03-25DOI: 10.30799/JNST.207.19050114
. P.JamilaJayanthi, I. Punithavathy, S. Jeyakumar, . T.Elavazhagan
Article history: Received 05 February 2019 Accepted 18 February 2019 Available online 25 March 2019 The preparation, optimization and application of biogenic nanomaterials have become the major division of study in nanotechnology. This study reports the single step; eco-friendly synthesis of silver nanoparticles using the aqueous extract of Tridax procumbens plant extracts with different extract concentrations (10 mL to 40 mL). The aqueous extract of Tridax procumbens showed significant potential for the fast reduction of silver ions without using any external agents. XRD pattern of Ag-NPs was indexed to face-centered cubic structure. The structural parameters of silver nanoparticles have been estimated and grain size ranged from 21 nm to 44 nm. The UV-vis absorbance spectrum was observed at 424 nm. The FT-IR analysis confirmed the secondary metabolites bind on surface of the AgNPs. SEM studies concluded morphological transformation of surface of the silver nanoparticles. Silver nanospheres were transformed in to rectangular silver nanosheets by increasing the extract concentration. Elemental silver formations were confirmed by EDAX studies. The antibacterial efficacies of synthesized nanosilver were carried out against different human bacterial pathogens and found to show significant activity. Bio-synthesis of Ag-NPs using Tridax procumbens appears to be cost effective, biodegradable and an alternative to conventional synthesis methods.
文章历史:生物纳米材料的制备、优化和应用已成为纳米技术研究的主要领域。本研究报告了单步;利用不同萃取浓度(10 mL ~ 40 mL)的原藜草植物萃取物的水萃取物环保合成纳米银。在不使用任何外源试剂的情况下，原曲草水提物具有快速还原银离子的潜力。Ag-NPs的XRD图谱为面心立方结构。测定了银纳米颗粒的结构参数，粒径范围为21 ~ 44 nm。在424 nm处观察其紫外-可见吸收光谱。FT-IR分析证实次级代谢物结合在AgNPs表面。扫描电镜研究了纳米银表面的形态变化。通过提高萃取物浓度，使银纳米球转化为矩形银纳米片。EDAX研究证实了元素银的形成。对合成的纳米银对不同的人类细菌病原体进行了抑菌实验，发现其具有显著的抑菌活性。生物合成Ag-NPs使用三甘蔗渣似乎具有成本效益，可生物降解和替代传统的合成方法。
{"title":"Structural and Surface Morphology Transformation of Plant Assisted Silver Nanoparticles and Its Biological Applications","authors":". P.JamilaJayanthi, I. Punithavathy, S. Jeyakumar, . T.Elavazhagan","doi":"10.30799/JNST.207.19050114","DOIUrl":"https://doi.org/10.30799/JNST.207.19050114","url":null,"abstract":"Article history: Received 05 February 2019 Accepted 18 February 2019 Available online 25 March 2019 The preparation, optimization and application of biogenic nanomaterials have become the major division of study in nanotechnology. This study reports the single step; eco-friendly synthesis of silver nanoparticles using the aqueous extract of Tridax procumbens plant extracts with different extract concentrations (10 mL to 40 mL). The aqueous extract of Tridax procumbens showed significant potential for the fast reduction of silver ions without using any external agents. XRD pattern of Ag-NPs was indexed to face-centered cubic structure. The structural parameters of silver nanoparticles have been estimated and grain size ranged from 21 nm to 44 nm. The UV-vis absorbance spectrum was observed at 424 nm. The FT-IR analysis confirmed the secondary metabolites bind on surface of the AgNPs. SEM studies concluded morphological transformation of surface of the silver nanoparticles. Silver nanospheres were transformed in to rectangular silver nanosheets by increasing the extract concentration. Elemental silver formations were confirmed by EDAX studies. The antibacterial efficacies of synthesized nanosilver were carried out against different human bacterial pathogens and found to show significant activity. Bio-synthesis of Ag-NPs using Tridax procumbens appears to be cost effective, biodegradable and an alternative to conventional synthesis methods.","PeriodicalId":23586,"journal":{"name":"Volume 5,Issue 1,2019","volume":"5 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-03-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82054592","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2019-03-20DOI: 10.30799/JNST.211.19050112
Tessy John, K. Parmar, P. Tak
Green synthesis of silver nanoparticles is one of the promising branches of nanotechnology for applications in different biomedical fields. In the present investigation, methanol extract of Tinospora cordifolia root were used as reducing agent. Then the silver nanoparticles are characterized using UV-Vis, SEM, XRD, TEM and FTIR spectroscopic techniques. The functional biomolecules responsible for the reduction of the silver ions and the capping of the silver nanoparticles by the plant extract Tinospora cordifolia were identified by the Fourier transform infrared spectroscopy (FTIR) analysis. The TEM analysis shows that the silver nanoparticles with an average size of 100 nm. X-ray diffraction analysis showed that the particles were crystalline in nature.
{"title":"Biosynthesis and Characterization of Silver Nanoparticles from Tinospora cordifolia Root Extract","authors":"Tessy John, K. Parmar, P. Tak","doi":"10.30799/JNST.211.19050112","DOIUrl":"https://doi.org/10.30799/JNST.211.19050112","url":null,"abstract":"Green synthesis of silver nanoparticles is one of the promising branches of nanotechnology for applications in different biomedical fields. In the present investigation, methanol extract of Tinospora cordifolia root were used as reducing agent. Then the silver nanoparticles are characterized using UV-Vis, SEM, XRD, TEM and FTIR spectroscopic techniques. The functional biomolecules responsible for the reduction of the silver ions and the capping of the silver nanoparticles by the plant extract Tinospora cordifolia were identified by the Fourier transform infrared spectroscopy (FTIR) analysis. The TEM analysis shows that the silver nanoparticles with an average size of 100 nm. X-ray diffraction analysis showed that the particles were crystalline in nature.","PeriodicalId":23586,"journal":{"name":"Volume 5,Issue 1,2019","volume":"90 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-03-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83552242","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2019-03-16DOI: 10.30799/JNST.175.19050111
S. Darbar, Srimoyee Saha, K. Pramanik, Atiskumar Chattopadhyay
Article history: Received 12 October 2018 Accepted 28 November 2018 Available online 16 March 2019 Nanomedicine is a combination of nanotechnology and medicine. It provides new direction in medical diagnosis, monitoring and treatment at the level of single molecules or molecular assemblies at the “nano” scale. Additionally, continuing improvement in the pharmacological and therapeutic properties of drugs is driving the revolution in novel drug delivery systems. Nanomedicine is widely explored nowadays for treatment of life threatening diseases, yet comes with various challenges and questions. The present study encapsulates the acute toxicological aspects of the Andrographis paniculata coupled with silver nanoparticles (AP-Ag NP). For acute toxicity studies according to OCED (Organization for Economic Cooperation and Development) guidelines Swiss Albino male mice (6-7 weeks) were used and were given single intraperitoneal dose of 2000 and 5000 mg/kg body weight of the AP-Ag nanoparticle and were observed for mortality and other side effects for 14 days. The individual components of the formulation, viz. silver oxide in surface modified nano form and at low dose, and Andrographis paniculata are both biocompatible materials. No changes were found for general appearance, behavior and body weight, thus concluding that the nanocomposite formulation does not have a single dose toxicity.
{"title":"Toxicological Assessment of Silver Nanoparticles Synthesized through Green Route using Andrographis paniculata","authors":"S. Darbar, Srimoyee Saha, K. Pramanik, Atiskumar Chattopadhyay","doi":"10.30799/JNST.175.19050111","DOIUrl":"https://doi.org/10.30799/JNST.175.19050111","url":null,"abstract":"Article history: Received 12 October 2018 Accepted 28 November 2018 Available online 16 March 2019 Nanomedicine is a combination of nanotechnology and medicine. It provides new direction in medical diagnosis, monitoring and treatment at the level of single molecules or molecular assemblies at the “nano” scale. Additionally, continuing improvement in the pharmacological and therapeutic properties of drugs is driving the revolution in novel drug delivery systems. Nanomedicine is widely explored nowadays for treatment of life threatening diseases, yet comes with various challenges and questions. The present study encapsulates the acute toxicological aspects of the Andrographis paniculata coupled with silver nanoparticles (AP-Ag NP). For acute toxicity studies according to OCED (Organization for Economic Cooperation and Development) guidelines Swiss Albino male mice (6-7 weeks) were used and were given single intraperitoneal dose of 2000 and 5000 mg/kg body weight of the AP-Ag nanoparticle and were observed for mortality and other side effects for 14 days. The individual components of the formulation, viz. silver oxide in surface modified nano form and at low dose, and Andrographis paniculata are both biocompatible materials. No changes were found for general appearance, behavior and body weight, thus concluding that the nanocomposite formulation does not have a single dose toxicity.","PeriodicalId":23586,"journal":{"name":"Volume 5,Issue 1,2019","volume":"4 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-03-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89931580","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2019-03-15DOI: 10.30799/JACS.204.19050103
E. Abadir, N. F. A. Salam, F. Barakat
In order to deduce the optimum conditions of chitosan production, a statistical model based on 23 full factorial design was used. The optimum conditions of deacetylation reaction were investigated using batch experiments technique. The investigated factors are NaOH concentration, time of the deacetylation reaction, and reaction temperature. A first order model was elaborated and a regression equation obtained that showed a strong determination coefficient (0.946). The kinetics of the reaction was studied and the order of deacetylation reaction was deduced and was found to be pseudo – first order law. Activation energy of the deacetylation reaction was found to be 3.86 kJ/mole.
{"title":"Study on Production and Kinetics of Chitosan from Shrimp Shell Waste using Factorial Design Experimental Technique","authors":"E. Abadir, N. F. A. Salam, F. Barakat","doi":"10.30799/JACS.204.19050103","DOIUrl":"https://doi.org/10.30799/JACS.204.19050103","url":null,"abstract":"In order to deduce the optimum conditions of chitosan production, a statistical model based on 23 full factorial design was used. The optimum conditions of deacetylation reaction were investigated using batch experiments technique. The investigated factors are NaOH concentration, time of the deacetylation reaction, and reaction temperature. A first order model was elaborated and a regression equation obtained that showed a strong determination coefficient (0.946). The kinetics of the reaction was studied and the order of deacetylation reaction was deduced and was found to be pseudo – first order law. Activation energy of the deacetylation reaction was found to be 3.86 kJ/mole.","PeriodicalId":23586,"journal":{"name":"Volume 5,Issue 1,2019","volume":"36 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-03-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90022604","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2019-02-11DOI: 10.30799/jacs.201.19050102
B. Mondal, M. Islam, Md. Emdad Hossain, M. Abser
Fly ash (FA), a coal combustion residue of thermal power plants has been regarded as a problematic solid waste all over the world. In this study FA samples were modified with NaOH and H2SO4. The mineralogical and microstructural characterization were carried out by means of X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy with energy dispersive X-ray spectroscopy (SEM/EDS) and Braunauer-Emmett-Tellers multilayer adsorption theory (BET). Experimental data showed that cenospheres were dominated with quartz and mullite glasses with both amorphous and crystalline phases. The acid treatment increased Si/Al ratios by removing impurities and dealuminations but alkali treatment significantly increased total pore volume. The specific surface area of alkali and acid treated samples were found 6.9 m2g-1 and 2.1 m2g-1 respectively, while that of virgin material was 1.5 m2g-1.
{"title":"Microstructural and Mineralogical Properties of Acid and Alkali Activated Coal Fly Ash","authors":"B. Mondal, M. Islam, Md. Emdad Hossain, M. Abser","doi":"10.30799/jacs.201.19050102","DOIUrl":"https://doi.org/10.30799/jacs.201.19050102","url":null,"abstract":"Fly ash (FA), a coal combustion residue of thermal power plants has been regarded as a problematic solid waste all over the world. In this study FA samples were modified with NaOH and H2SO4. The mineralogical and microstructural characterization were carried out by means of X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy with energy dispersive X-ray spectroscopy (SEM/EDS) and Braunauer-Emmett-Tellers multilayer adsorption theory (BET). Experimental data showed that cenospheres were dominated with quartz and mullite glasses with both amorphous and crystalline phases. The acid treatment increased Si/Al ratios by removing impurities and dealuminations but alkali treatment significantly increased total pore volume. The specific surface area of alkali and acid treated samples were found 6.9 m2g-1 and 2.1 m2g-1 respectively, while that of virgin material was 1.5 m2g-1.","PeriodicalId":23586,"journal":{"name":"Volume 5,Issue 1,2019","volume":"5 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-02-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85841193","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2019-02-07DOI: 10.30799/jnst.206.19050108
.. H.S.Gavale, .. M.S.Wagh, .. R.B.Ahirrao, S. R. Gosavi
Article history: Received 12 January 2019 Accepted 27 January 2019 Available online 07 February 2019 In this paper a systematic study has been carried out on the influence of thickness on the physical properties of nanocrystalline nickel oxide (NiO) thin films prepared on glass substrate by spray pyrolysis method. The prepared nanocrystalline NiO films were characterized using X-ray diffraction technique (XRD), field emission scanning electron microscopy (FESEM) and optical measurement techniques. XRD patterns reveal the cubic structure for all the samples and the crystallite size varies with the thickness. FESEM images confirmed that all the films are homogeneous, without any crack, dense and exhibit almost complete coverage of the substrate. The optical parameters such as transmittance, absorption coefficient and energy band gap of the films as a function of film thickness was investigated by UV-Vis spectrophotometer. The band gap of the films is found to be direct allowed transition and the variation of band gap values of nanocrystalline NiO thin films were found to be in the range of 3.48 eV to 3.53 eV.
本文系统研究了厚度对喷雾热解法制备纳米晶氧化镍(NiO)薄膜物理性能的影响。采用x射线衍射技术(XRD)、场发射扫描电镜(FESEM)和光学测量技术对制备的纳米晶NiO薄膜进行了表征。XRD图谱显示，所有样品均为立方结构，晶粒尺寸随厚度的变化而变化。FESEM图像证实，所有薄膜都是均匀的，没有任何裂纹，致密，几乎完全覆盖了衬底。利用紫外可见分光光度计研究了薄膜的透光率、吸收系数和能带隙等光学参数随薄膜厚度的变化规律。发现薄膜的带隙是直接允许跃迁的，纳米晶NiO薄膜带隙值的变化范围在3.48 eV ~ 3.53 eV之间。
{"title":"Study of Physical Properties of Nanocrystalline NiO Thin Films Prepared by Spray Pyrolysis Technique","authors":".. H.S.Gavale, .. M.S.Wagh, .. R.B.Ahirrao, S. R. Gosavi","doi":"10.30799/jnst.206.19050108","DOIUrl":"https://doi.org/10.30799/jnst.206.19050108","url":null,"abstract":"Article history: Received 12 January 2019 Accepted 27 January 2019 Available online 07 February 2019 In this paper a systematic study has been carried out on the influence of thickness on the physical properties of nanocrystalline nickel oxide (NiO) thin films prepared on glass substrate by spray pyrolysis method. The prepared nanocrystalline NiO films were characterized using X-ray diffraction technique (XRD), field emission scanning electron microscopy (FESEM) and optical measurement techniques. XRD patterns reveal the cubic structure for all the samples and the crystallite size varies with the thickness. FESEM images confirmed that all the films are homogeneous, without any crack, dense and exhibit almost complete coverage of the substrate. The optical parameters such as transmittance, absorption coefficient and energy band gap of the films as a function of film thickness was investigated by UV-Vis spectrophotometer. The band gap of the films is found to be direct allowed transition and the variation of band gap values of nanocrystalline NiO thin films were found to be in the range of 3.48 eV to 3.53 eV.","PeriodicalId":23586,"journal":{"name":"Volume 5,Issue 1,2019","volume":"14 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-02-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76803603","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2019-02-07DOI: 10.30799/jacs.202.19050101
. T.SumithaCelin, . G.AllenGnanaRaj
Binding of tris(2,2′−dimethoxy−2,2′−bipyriyl) ruthenium (II) complex with quinones have been studied in 50% aqueous acetonitrile medium by means of absorption spectral technique. The absorption and emission maximum of [Ru(dmeObpy)3] 2+ complex are 468 nm and 606 nm respectively. The binding constants for the reactions of the complex with quinones are determined using the Benesi-Hildebrand plot using the absorption intensity data. The value of Kb is sensitive to the structure and nature of the quenchers used. Structural effect also plays a significant role on the binding of the complex with quinones.
{"title":"Binding of Tris(4,4’-dimethoxy-2,2’-bipyridyl)ruthenium(II) Cation with Quinones in 50% Aqueous Acetonitrile","authors":". T.SumithaCelin, . G.AllenGnanaRaj","doi":"10.30799/jacs.202.19050101","DOIUrl":"https://doi.org/10.30799/jacs.202.19050101","url":null,"abstract":"Binding of tris(2,2′−dimethoxy−2,2′−bipyriyl) ruthenium (II) complex with quinones have been studied in 50% aqueous acetonitrile medium by means of absorption spectral technique. The absorption and emission maximum of [Ru(dmeObpy)3] 2+ complex are 468 nm and 606 nm respectively. The binding constants for the reactions of the complex with quinones are determined using the Benesi-Hildebrand plot using the absorption intensity data. The value of Kb is sensitive to the structure and nature of the quenchers used. Structural effect also plays a significant role on the binding of the complex with quinones.","PeriodicalId":23586,"journal":{"name":"Volume 5,Issue 1,2019","volume":"31 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-02-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80952192","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2019-02-04DOI: 10.30799/JNST.205.19050107
M. Karthikeyan, A. Ahamed, P. Kumar
In green nanotechnology, plant is used for the synthesis of nanoparticles which are gaining considerable interest among researchers as an eco-friendly alternative to conventional physical and chemical methods, as this approach eliminates the use of toxic chemicals. The present study describes the synthesis of Mg2+ (magnesium) doped zinc oxide (ZnO) nanoparticles (NPs) M1 using leaves extract of Gymnema sylvestre (G. sylvestre) belonging to Asclepiadaceae family and M2 using Mangifera indica (M. indica) belonging to Anacardiaceae family as reducing as well as capping agents. The obtained Mg2+ doped ZnO NPs (M1 and M2) were characterized by X-ray diffraction (XRD) studies, field emission scanning electron microscopy (FESEM), elemental analysis (EDAX), Fourier transform infrared spectroscopy (FTIR), UV-vis spectroscopy and photoluminescence (PL) spectra.
{"title":"Optical and Structural Investigation of Mg2+ doped ZnO Nanoparticles using Gymnema sylvestre and Mangifera indica Leaves Extracts","authors":"M. Karthikeyan, A. Ahamed, P. Kumar","doi":"10.30799/JNST.205.19050107","DOIUrl":"https://doi.org/10.30799/JNST.205.19050107","url":null,"abstract":"In green nanotechnology, plant is used for the synthesis of nanoparticles which are gaining considerable interest among researchers as an eco-friendly alternative to conventional physical and chemical methods, as this approach eliminates the use of toxic chemicals. The present study describes the synthesis of Mg2+ (magnesium) doped zinc oxide (ZnO) nanoparticles (NPs) M1 using leaves extract of Gymnema sylvestre (G. sylvestre) belonging to Asclepiadaceae family and M2 using Mangifera indica (M. indica) belonging to Anacardiaceae family as reducing as well as capping agents. The obtained Mg2+ doped ZnO NPs (M1 and M2) were characterized by X-ray diffraction (XRD) studies, field emission scanning electron microscopy (FESEM), elemental analysis (EDAX), Fourier transform infrared spectroscopy (FTIR), UV-vis spectroscopy and photoluminescence (PL) spectra.","PeriodicalId":23586,"journal":{"name":"Volume 5,Issue 1,2019","volume":"93 3 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-02-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83338682","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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