@article { ISI:000252406100012, title = {CdS quantum dots: enzyme mediated in vitro synthesis, characterization and conjugation with plant lectins}, journal = {Journal of Biomedical Nanotechnology}, volume = {3}, number = {4}, year = {2007}, month = {DEC}, pages = {406-413}, publisher = {AMER SCIENTIFIC PUBLISHERS}, type = {Article}, address = {25650 NORTH LEWIS WAY, STEVENSON RANCH, CA 91381-1439 USA}, abstract = {

This paper presents the in vitro synthesis of CdS quantum dot nanoparticles using sulphite reductase and capping peptide in the presence of a co-factor alpha-NADPH, their characterization and conjugation with plant lectins, Jacalin and Chick pea lectin. Incubation of sulphite reductase with aqueous CdCl2, Na2SO3, and capping peptide in the presence of a-NADPH, which acts as a co-factor, resulted in the formation of CdS nanoparticles of dimensions 5-20 nm. These CdS nanoparticles were conjugated with plant lectins by EDAC mediated coupling. These observations are of significance, as it will help in the development of eco-friendly process for the formation of CdS nanoparticles and their application as fluorescent biolabels. Moreover the above studies will also help in designing a rational enzymatic strategy for the synthesis of nanomaterials of different chemical composition, shapes and sizes as well as their separation.

}, keywords = {bio-label, CdS quantum dots, conjugation, Enzyme, in vitro synthesis, Nanoparticles}, issn = {1550-7033}, doi = {10.1166/jbn.2007.045}, author = {Ansary, Abu Ayoobul and Kumar, S. Anil and Krishnasastry, M. V. and Abyaneh, Majid Kazemian and Kulkarni, Sulabha K. and Ahmad, Absar and Khan, Mohammad Islam} } @article { ISI:000244293000015, title = {Nitrate reductase-mediated synthesis of silver nanoparticles from AgNO3}, journal = {Biotechnology Letters}, volume = {29}, number = {3}, year = {2007}, month = {MAR}, pages = {439-445}, publisher = {SPRINGER}, type = {Article}, address = {VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS}, abstract = {

Synthesis of silver nanoparticles using alpha-NADPH-dependent nitrate reductase and phytochelatin in vitro has been demonstrated for the first time. The silver ions were reduced in the presence of nitrate reductase, leading to the formation of a stable silver hydrosol 10-25 nm diam. and stabilized by the capping peptide. The nanoparticles were characterized by X-ray diffraction, transmission electron microscopy, X-ray photoelectron spectroscopy and UV-Vis absorption. These studies will help in designing a rational enzymatic strategy for the synthesis of nanomaterials of different chemical composition, shapes and sizes as well as their separation.

}, keywords = {Capping Peptide, enzymatic method, nitrate reductase, silver nanoparticles}, issn = {0141-5492}, doi = {10.1007/s10529-006-9256-7}, author = {Kumar, S. Anil and Abyaneh, Majid Kazemian and Gosavi, S. W. and Kulkarni, Sulabha K. and Pasricha, Renu and Ahmad, Absar and Khan, Mohammad Islam} } @article { ISI:000258370500013, title = {New route for preparation of luminescent mercaptoethanoate capped cadmium selenide quantum dots}, journal = {Bulletin of Materials Science}, volume = {31}, number = {3}, year = {2008}, note = {National Review and Coordination Meeting on Nanoscience and Nanotechnology, Hyderabad, INDIA, 2007}, month = {JUN}, pages = {291-296}, publisher = {INDIAN ACAD SCIENCES}, address = {C V RAMAN AVENUE, SADASHIVANAGAR, P B \#8005, BANGALORE 560 080, INDIA}, abstract = {

We report a synthesis of cadmium selenide quantum dots (Q-CdSe) by refluxing a mixture of cadmium acetate, selenium powder, sodium sulfite and 2-mercaptoethanol in N,N{\textquoteright}-dimethyl formamide (DMF)/water solution. X-ray and electron diffractions suggest the formation of hexagonal phase of size quantized CdSe. Based on TEM analysis, the formation of nanoparticles with an average diameter of 3.5 +/- 0.5 nm is inferred. Their sols in DMF and dimethyl sulphoxide (DMSO) gave characteristic absorption peaks at 300 nm and 327 nm, which is attributed to the formation of high quality, size quantized CdSe particles. Extracted particles from the sol were readily redispersed in DMF and DMSO, which were diluted further with water without losing their optical and colloidal properties. FTIR spectroscopy suggested the formation of 2-mercaptoethanol thiolate on the particle surface, with free -OH groups available for linkage. Sols in DMSO and their solutions in water displayed an intense photoluminescence (PL).

}, keywords = {chalcogenides, Chemical synthesis, photoluminescence, semiconductor quantum dots}, issn = {0250-4707}, doi = {10.1007/s12034-008-0047-8}, author = {Wankhede, Manoj E. and Inamdar, Shaukatali N. and Deshpande, Aparna and Thete, Aniket R. and Pasricha, Renu and Kulkarni, Sulabha K. and Harani, Santosh K.} } @article { ISI:000262886200019, title = {Epitaxially grown zinc-blende structured Mn doped ZnO nanoshell on ZnS nanoparticles}, journal = {Materials Research Bulletin}, volume = {44}, number = {2}, year = {2009}, month = {FEB}, pages = {339-344}, publisher = {PERGAMON-ELSEVIER SCIENCE LTD}, address = {THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND}, abstract = {

Zinc oxide in the bulk as well as in the nanocrystalline form is thermodynamically stable in the wurtzite structure. However, zinc oxide in the zinc-blende structure is more useful than that in the wurtzite structure due to its superior electronic properties as well as possibility of efficient doping. Therefore, zinc oxide shell is grown epitaxially on zinc sulphide core nanoparticles having zinc-blende structure. It is shown that doping of manganese could be achieved in zinc oxide nanoshell with zinc-blende structure. (C) 2008 Elsevier Ltd. All rights reserved.

}, keywords = {Chemical synthesis, Luminescence, Nanostructures, Semiconductors, X-ray diffraction}, issn = {0025-5408}, doi = {10.1016/j.materresbull.2008.05.015}, author = {Limaye, Mukta V. and Singh, Shashi B. and Date, Sadgopal K. and Gholap, Ramkrishna S. and Kulkarni, Sulabha K.} } @article { ISI:000287268900024, title = {Room temperature ferromagnetism in undoped and Fe doped ZnO nanorods: microwave-assisted synthesis}, journal = {Journal of Solid State Chemistry}, volume = {184}, number = {2}, year = {2011}, month = {FEB}, pages = {391-400}, publisher = {ACADEMIC PRESS INC ELSEVIER SCIENCE}, address = {525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA}, abstract = {

One-dimensional (1D) undoped and Fe doped ZnO nanorods of average length similar to 1 mu m and diameter similar to 50 nm have been obtained using a microwave-assisted synthesis. The magnetization (M) and coercivity (H-c) value obtained for undoped ZnO nanorods at room temperature is similar to 5 X 10(-3) emu/g and similar to 150 Oe, respectively. The Fe doped ZnO samples show significant changes in M -H loop with increasing doping concentration. Both undoped and Fe doped ZnO nanorods exhibit a Curie transition temperature (T-c) above 390 K. Electron spin resonance and Mossbauer spectra indicate the presence of ferric ions. The origin of ferromagnetism in undoped ZnO nanorods is attributed to localized electron spin moments resulting from surface defects/vacancies, where as in Fe doped samples is explained by F center exchange mechanism. (C) 2010 Published by Elsevier Inc.

}, keywords = {Diluted magnetic semiconductors, Nanostructures, ZnO}, issn = {0022-4596}, doi = {10.1016/j.jssc.2010.11.008}, author = {Limaye, Mukta V. and Singh, Shashi B. and Das, Raja and Poddar, Pankaj and Kulkarni, Sulabha K.} } @article { ISI:000308631300056, title = {Observation of enhanced dielectric coupling and room-temperature ferromagnetism in chemically synthesized BiFeO3@SiO2 core-shell particles}, journal = {Journal of Physical Chemistry C}, volume = {116}, number = {36}, year = {2012}, month = {SEP}, pages = {19503-19511}, publisher = {AMER CHEMICAL SOC}, address = {1155 16TH ST, NW, WASHINGTON, DC 20036 USA}, abstract = {

We report the effect of SiO2 coating on the structural, magnetic, and dielectric properties of chemically synthesized high-purity BiFeO3 particles. The assynthesized BiFeO3 particles demonstrate properties comparable with those reported for bulk BiFeO3. On the other hand, the structural measurement on BiFeO3@SiO2 shows that the SiO2 coating has anisotropically compressed the lattice of BiFeO3 particles and stimulates the variation in the electron density. This affects magnetic and dielectric behavior of material. Frequency-dependent dielectric constant study at low temperature (20-325 K) revealed slight reduction (8-10\%) in the dielectric constant of BiFeO3@SiO2 particles compared to uncoated BiFeO3 particles. The study reveals five anomalies at 234, 206, 146, 84, and 25 K located in close proximity to the linear magnetodielectric coupling and spin reorientation transitions. The loss tangent (approximate to 10(-3)) and alternating current (ac) conductivity (approximate to 10(-8) Omega(-1)cm(-1)) of BiFeO3@SiO2 particles are orders of magnitude lower than those observed for the BiFeO3 particles. The magnetic measurement shows the existence of room-temperature ferromagnetism in BiFeO3@SiO2 particles with average value of magnetic moment per Fe atom approximate to 0.030 mu(B) and appreciable coercivity as high as 120 Oe. The canted spin structure in the surface shell of BiFeO3@SiO2 particles show an enhanced magnetic property and shifted hysteresis loop. The magnetic measurement in close proximity to dielectric transitions revealed enhanced magnetization, suggesting the presence of anisotropies. It has been observed that SiO2 coating alters the properties of BiFeO3 particles. Our dielectric and magnetic measurements show enhanced coupling among the electric and magnetic ordered parameters in BiFeO3@SiO2 core-shell particles compared to uncoated BiFeO3 particles. The magnetic and dielectric properties of SiO2-coated BiFeO3 are similar to nanoparticles of BiFeO3 where interface plays a significant role.

}, issn = {1932-7447}, doi = {10.1021/jp3025683}, author = {Shirolkar, Mandar M. and Das, Raja and Maity, Tuhin and Poddar, Pankaj and Kulkarni, Sulabha K.} } @article {48689, title = {Self-powered wearable breath sensor cum nanogenerator using AuNR-rGO-PVDF nanocomposite}, journal = {IEEE Sensors Journal}, volume = {23}, year = {2023}, month = {APR }, pages = {6473-6480}, type = {Article}, abstract = {

Breathing is the most important function of living being. It is well known that breath contains 90\% humidity along with various gases and volatile organic compounds (VOCs). These gases are released during various metabolic activities in the body. These gases present in the breath can act as biomarkers to showcase healthiness or abnormalities in the body. Therefore, breath sensors are the need of time to detect diseases at early stages and in noninvasive way. Herein, we report, simple breath sensor using Au nanorods (AuNRs) and its nanocomposite with reduced graphene oxide (rGO) and polyvinylidene fluoride (PVDF). The nanocomposites system is designed in such a way that each component has its advantages for breath sensing. Here, AuNR being a good humidity sensitive material detects the breath efficiently. The ss phased PVDF being a very good ferroelectric material, contributes for voltage generation during sensing and enables the device to be self powered. The highly conducting rGO increases the sensitivity and voltage generation by facilitating the electron transport in the nanocomposite system. The nanocomposite was optimized with respect to PVDF, rGO and Au concentration. The as-synthesized materials were characterized by physiochemical characterization techniques such as field emission scanning electron microscopy (FESEM), X-ray diffraction analysis (XRD), UV-Visible spectroscopy, Fourier transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS). The ss phase formation of the PVDF was confirmed from the XRD peak at 20.41 degrees. SEM results revealed that AuNR have length 15-20 nm and aspect ratio similar to 3-4. Breath sensing tests were carried out for as synthesized nanocomposite material. The nanocomposite exhibited high sensitivity towards breath and generated the voltage of similar to 0.7 V within 0.8 s.

}, keywords = {Au nanorods (AuNRs), breath analyzer, breath sensor, nanogenerator}, issn = {1530-437X}, doi = {10.1109/JSEN.2023.3240744}, author = {Bang, Amruta D. and Ghalawat, Monika and Poddar, Pankaj and Kulkarni, Sulabha K. and Adhyapak, Parag V.} }