Single-walled Carbon Nanotube-triethylammonium Ionic Liquid as a New Catalytic System for Michael Reaction

Attri, Pankaj,Choi, Eun Ha,Kwon, Gi-Chung,Bhatia, Rohit,Gaur, Jitender,Arora, Bharti,Kim, In Tae Korean Chemical Society 2014 Bulletin of the Korean Chemical Society Vol.35 No.10

A new efficient catalytic method for aza/thia-Michael addition reactions of amines/thiols with higher product yields has been developed. Combining single-walled carbon nanotubes (SWCNT) with triethylammonium hydrogen phosphate (TEAP) ionic liquid (IL) can work as a catalyst. We utilized Raman spectroscopy to gain insight into the interactions between IL and SWCNT. The interactions between SWCNT with TEAP were confirmed by the increasing intensity ratios and spectral shift in wavelength of the Raman D and G bands of SWCNT. Further, the morphology of the resulting composite materials of TEAP and SWCNT was determined by using scanning electron microscopy (SEM). Higher product yield in reduced reaction time is the key advantage of using bucky gel as a catalyst for Michael reaction.

Plasma modification of poly(2-heptadecyl-4-vinylthieno[3,4-<i>d</i>]thiazole) low bandgap polymer and its application in solar cells

Attri, Pankaj,Bharti, Vishal,Kim, Young Sun,Gaur, Jitender,Chand, Suresh,Kwon, Gi-Chung,Lee, Seung-Hyun,Lee, Weontae,Choi, Eun Ha,Kim, In Tae The Royal Society of Chemistry 2014 Physical chemistry chemical physics Vol.16 No.48

<P>For the first time, we here propose a green methodology to modify a low bandgap polymer for highly efficient solar cells using atmospheric pressure plasma jet or soft plasma operating on different feeding gases (air, Ar and N<SUB>2</SUB>). The physical properties of the modified polymer were investigated using conductivity measurements, UV-visible spectroscopy, photoluminescence spectroscopy, X-ray photoelectron spectroscopy, cyclic voltammograms, atomic force microscopy, cathodoluminescence and confocal Raman spectroscopy. Further, we examined the variation of the work function of the polymer before and after plasma treatment using a γ-focused ion beam. Additionally, photovoltaic cells based on the plasma-modified polymer having ITO/PEDOT:PSS/PHVTT (with or without plasma modification):PC<SUB>71</SUB>BM/LiF/Al configuration were fabricated and then characterized. We found that the power conversion efficiency (PCE) of the plasma-modified polymer increased dramatically as compared to the control polymer (without plasma treatment). PCE of the control polymer was found to be 4.11%, while after air, Ar and N<SUB>2</SUB> gas plasma treatment the polymer showed PCEs of 4.85%, 4.87% and 5.14% respectively. Thus, plasma treatment not only alters the surface properties, but also modifies the bulk properties (changes in HOMO and LUMO bandgap level). Hence, this work provides new dimensions to explore more about plasma and polymer chemistry.</P> <P>Graphic Abstract</P><P>The increase in power conversion efficiency (PCE) of bulk heterojunction photovoltaic cells in the presence of a plasma-modified polymer. <IMG SRC='http://pubs.rsc.org/services/images/RSCpubs.ePlatform.Service.FreeContent.ImageService.svc/ImageService/image/GA?id=c4cp03323j'> </P>

Effect of temperature on the interactions between low bandgap polymer and ionic liquids

Attri, P.,Lee, S.H.,Hwang, S.W.,Kim, J.I.,Jang, W.,Kim, Y.B.,Park, J.H.,Kwon, G.C.,Choi, E.H.,Kim, I.T. Elsevier 2014 Thermochimica acta Vol.579 No.-

In this paper, we have examined the effect of temperature on the interactions between imidazolium and ammonium based ionic liquids (ILs) and the low bandgap polymer (poly(2-heptadecyl-4-vinylthieno[3,4-d]thiazole) (PHVTT)). With the aim of exploring the utility of low bandgap polymers, we have carried out the interaction studies of the polymer with the ILs and investigated the behavior of polymer in the presence of ILs as the function of temperature. Recently, ILs have attracted extensive attention in polymer sciences. In this work, we have studied the temperature dependent interactions between the protic IL (1-methylimidazolium chloride ([Mim]Cl) from imidazolium family) and aprotic ILs (tributylmethylammonium methyl sulfate ([N<SUB>1444</SUB>][MeSO<SUB>4</SUB>]) from ammonium family and 1-butyl-3-methylimidazolium chloride ([Bmim]Cl) from imidazolium family) with a low bandgap polymer. Our experimental data of UV-vis spectroscopy, photoluminescence (PL) spectroscopy, FT-IR spectroscopy, density (ρ) and speed of sound (u) as a function of temperature from 25 to 40<SUP>o</SUP>C with the interval of 5<SUP>o</SUP>C, clearly reveal that even at high temperature, [Bmim]Cl interacts strongly with the polymer as compared to other studied ILs.

Triethylammonium acetate ionic liquid assisted one-pot synthesis of dihydropyrimidinones and evaluation of their antioxidant and antibacterial activities

Attri, P.,Bhatia, R.,Gaur, J.,Arora, B.,Gupta, A.,Kumar, N.,Choi, E.H. Elsevier ; King Saud University 2017 Arabian journal of chemistry Vol.10 No.2

<P>A mild and efficient catalytic method has been developed to synthesize 3,4-dihydropyrimidinones in high yield by one-pot three component Biginelli condensation in the presence of triethylammonium acetate (TEAA) which acts as catalyst/reaction medium. Further, we have studied the antioxidant and antibacterial activities of these synthesized 3,4-dihydropyrimidinones. All the synthesized compounds reveal the significant antioxidant properties, these properties have been studied using 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical scavenging and cupric reducing antioxidant capacity (CUPRAC) assays. In addition, to this, these compounds also show the good antibacterial activity against four human pathogenic bacteria. (C) 2014 King Saud University. Production and hosting by Elsevier B.V.</P>

Impact of an ionic liquid on protein thermodynamics in the presence of cold atmospheric plasma and gamma rays

Attri, Pankaj,Kim, Minsup,Choi, Eun Ha,Cho, Art E.,Koga, Kazunori,Shiratani, Masaharu The Royal Society of Chemistry 2017 Physical chemistry chemical physics Vol.19 No.37

<▼1><P>TEMS IL can protect proteins against the reactive species generated by gamma rays and plasma.</P></▼1><▼2><P>Cold atmospheric plasma and gamma rays are known to have anticancer properties, even though their specific mechanisms and roles as co-solvents during their action are still not clearly understood. Despite the use of gamma rays in cancer therapy, they have oncogenic potential, whereas this has not been observed for plasma treatment (to date). To gain a better understanding, we studied the action of dielectric barrier discharge (DBD) plasma and gamma rays on the myoglobin protein. We analyzed the secondary structure and thermodynamic properties of myoglobin after both treatments. In addition, in the last few years, ammonium ionic liquids (ILs) have revealed their important role in protein folding as co-solvents. In this work, we treated the protein with ammonium ILs such as triethylammonium methanesulfonate (TEMS) and tetrabutylammonium methanesulfonate (TBMS) and later treated this IL–protein solution with DBD plasma and gamma rays. In this study, we show the chemical and thermal denaturation of the protein after plasma and gamma treatments in the presence and absence of ILs using circular dichroism (CD) and UV-vis spectroscopy. Furthermore, we also show the influence of plasma and gamma rays on the secondary structure of myoglobin in the absence and presence of ILs or ILs + urea using CD. Finally, molecular dynamic simulations were conducted to gain deeper insight into how the ILs behave to protect the protein against the hydrogen peroxide generated by the DBD plasma and gamma rays.</P></▼2>

Effects of Atmospheric-pressure Non-thermal Plasma Jets on Enzyme Solutions

Pankaj Attri,Pannuru Venkatesu,Kaushik NAgendra Kumar,Yong Gyu Han,Chul Joo Nam,최은하,김기선 한국물리학회 2012 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.60 No.6

In order to study the wide scope of structural information of biomolecules in the presence of biocompatible cold atmospheric pressure plasma jets (CAPJ), we used circular dichroism (CD) and fluorescence experiments. Biomolecules are very sensitive and are highly complex systems, exhibiting a substantial degree of structural variability in their folded state. In the present investigation, we compared the compatiblity of -chymotrypsin (CT) in the presence of biocompatible CAPJ. Using circular dichroism (CD) and fluorescence experiments, we describe the associated structural changes in CT after a 5 min treatment with CAPJ. The modifications in the secondary structure of this β/β protein were quantified by using the CD spectra. A reasonable decrease was observed for β-strands after treatment with CAPJ as compared to buffer, which contributes to its deterioration power. The implications of our results from studies delineating the effects of CAPJ on enzyme solutions are discussed.

Development and diversity of lactic acid producing bacteria and bifidobacteria in healthy full term Indian infants from Himachal Pradesh

( Sampan Attri ),( Rishi Mahajan ),( Gunjan Goel ) 대한장연구학회 2018 Intestinal Research Vol.16 No.4

Background/Aims: The initial microbial colonization is a crucial step for the healthy development of an infant. Previous studies from India reported the dominance of target microbial species among Indian infants without any analysis on the diversity of target groups. This is the first study from India with an objective to investigate the establishment and diversity of lactic acid producing bacteria (LAB) and bifidobacteria in vaginally delivered, full term, breastfed infants for the first 4 months after birth. Methods: Present study used polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE) based sequence analysis of LAB and bifidobacteria in healthy infants. The results were used to compare the development and early colonization by LAB and bifidobacteria using diversity indices during the initial months of development of gut microbiota in infants. Results: During the first 4 months, the Shannon diversity index (H) of LAB increased from 1.16 to 1.318 and for bifidobacteria the H increased from 0.975 to 1.293 (P<0.05). Higher Sorenson’s pair wise similarity coefficient was observed for LAB and bifidobacteria during 2nd and the 3rd month. The species of the genera Enterococcus, Streptococcus, and Lactobacillus were dominant among the LAB group whereas Bifidobacterium breve was dominant species among Bifidobacterium group. Conclusions: Our results indicate that in breast fed infants, the microbial diversity of LAB and bifidobacteria increased during the period of study. (Intest Res 2018;16:529-536)

Action of atmospheric pressure non-thermal plasma on the biomolecules and bio-organism

Pankaj Attri,Ji Hoon Park,Naresh Kumar,Anser Ali,In Tae Kim,Weontae Lee,Eun Ha Choi 한국진공학회 2015 한국진공학회 학술발표회초록집 Vol.2015 No.8

Single-walled Carbon Nanotube-triethylammonium Ionic Liquid as a New Catalytic System for Michael Reaction

Pankaj Attri,최은하,권기청,Rohit bhatia,Jitender Gaur,Bharti Arora,김인태 대한화학회 2014 Bulletin of the Korean Chemical Society Vol.35 No.10

A new efficient catalytic method for aza/thia-Michael addition reactions of amines/thiols with higher product yields has been developed. Combining single-walled carbon nanotubes (SWCNT) with triethylammonium hydrogen phosphate (TEAP) ionic liquid (IL) can work as a catalyst. We utilized Raman spectroscopy to gain insight into the interactions between IL and SWCNT. The interactions between SWCNT with TEAP were confirmed by the increasing intensity ratios and spectral shift in wavelength of the Raman D and G bands of SWCNT. Further, the morphology of the resulting composite materials of TEAP and SWCNT was determined by using scanning electron microscopy (SEM). Higher product yield in reduced reaction time is the key advantage of using bucky gel as a catalyst for Michael reaction.

Post-Pollination Biochemical Changes in the Floral Organs of Rhynchostylis retusa (L.) Bl. and Aerides multiflora Roxb (Orchidaceae)

( Lucky Kumar Attri ),( Harsh Nayyar ),( Ravinder Kumar Bhanwra ),( Suraj Prakash Vij ) 한국식물학회 2007 Journal of Plant Biology Vol.50 No.5

If left unpollinated, the flowers of Aerides multiflora (Roxb.) and Rhynchostylis retusa (L.) Bl. can remain fresh for 17 and 24 d, respectively. However, they begin to wilt at 2 to 3 days after pollination (DAP) and 3 to 4 DAP, respectively, and become senescent at 5 DAP and 7 DAP, respectively. When measured at two developmental phases - Stage 1, start of wilting and Stage 2, progression to senescence - all the floral organs from pollinated flowers had higher contents of total soluble sugars, reducing sugars, and free amino acids than those from unpollinated flowers. A corresponding increase was noted in the activities of hydrolytic enzymes, i.e., α-amylase, β-amylase, and invertase, and proteolytic enzymes (proteases) in those organs. This indicated that signals related to pollination had up-regulated those activities, leading to a breakdown of complex molecules into simpler ones for mobilization. The amounts of sugars and enzyme activity were relatively greater in the pollinated flowers of A. multiflora compared with R. retusa, and levels were always higher in the floral lips and perianths. When inhibitors of auxin (0.25mM TIBA) or ethylene (0.25 mM AgNO3) were applied to the pollinated flowers, their senescence was partially prevented, thus signifying hormonal involvement in governing the pollination-induced biochemical alterations normally found in those organs.