@article { ISI:000243655000034, title = {Blocking effects in irreversible adsorption of linear macromolecules}, journal = {Surface Science}, volume = {601}, number = {1}, year = {2007}, month = {JAN}, pages = {274-279}, publisher = {ELSEVIER SCIENCE BV}, type = {JAN}, address = {PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS}, abstract = {

{A new variant of random sequential adsorption (RSA), namely random sequential ballistic adsorption (RSBA), is proposed to explore the possible role of blocking effects in the adsorption dynamics of ballistically arriving objects. These objects upon adsorption can protrude outside the substrate and in turn can obstruct and hence reject the adsorption of newly arriving objects. Adsorption of linear macromolecules (modeled as infinitesimally thin needles), on a two-dimensional continuum substrate is studied using RSBA model. It is shown analytically that in late time regime, the number n(t) of adsorbed objects at time t follows a power law n(t) similar to t(alpha), as in RSA, but with a different exponent

}, keywords = {Adsorption, adsorption kinetics, Monte Carlo simulations, random sequential adsorption (RSA)}, issn = {0039-6028}, doi = {10.1016/j.susc.2006.09.031}, author = {Shelke, Pradip B. and Banpurkar, Arun G. and Ogale, S. B. and Limaye, A. V.} } @article { ISI:000251153900031, title = {Impact of orientational distribution of adsorbing objects on dynamics of Random Sequential Ballistic Adsorption (RSBA) dynamics}, journal = {Surface Science}, volume = {601}, number = {21}, year = {2007}, month = {NOV}, pages = {5010-5015}, publisher = {ELSEVIER SCIENCE BV}, type = {Article}, address = {PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS}, abstract = {

Recently, by proposing a new variant of Random Sequential Adsorption (RSA) namely Random Sequential Ballistic Adsorption (RSBA) model [Pradip B. Shelke, A.G. Banpurkar, S.B. Ogale, A.V. Limaye, Surf. Sci. 601 (2007) 274], we addressed the issue of adsorption dynamics of extended objects where the objects, upon adsorption, protrude outside the substrate. This study brought out the role of the arriving trajectory in the adsorption dynamics. In the present work the possible role of the orientational distribution of the arriving objects in the RSBA dynamics is investigated. The dynamics of RSBA of needles (line segments) is studied analytically and by computer simulation for different types of theta distributions of arriving needles, theta being the angle made by the arriving needle with normal to the substrate. Three types of theta distributions, namely a uniform distribution over the range (0, pi/2), a Gaussian distribution and a distribution uniform over the solid angle, are considered. Analytical treatment establishes that in all the three cases, the number n(t) of adsorbed objects at a late time t follows a power law n(t) similar to t(alpha), and the exponent a depends on the specifics of the theta distribution. In general, for distribution f(theta) proportional to theta(beta), for theta -\> 0, alpha is found to be 2/(beta + 3). The simulation results are in excellent agreement with the analytical findings and together they reveal that the orientational distribution of arriving objects has significant consequences for the Random Sequential Ballistic Adsorption (RSBA) process. (C) 2007 Elsevier B.V. All rights reserved.

}, keywords = {Adsorption, adsorption kinetics, Monte Carlo simulations, random sequential adsorption (RSA)}, issn = {0039-6028}, author = {Shelke, Pradip B. and Banpurkar, Arun G. and Ogale, Satishchandra B. and Limaye, A. V.} } @article { ISI:000268650600020, title = {On the change in bacterial size and magnetosome features for magnetospirillum magnetotacticum (MS-1) under high concentrations of zinc and nickel}, journal = {Biomaterials}, volume = {30}, number = {25}, year = {2009}, month = {SEP}, pages = {4211-4218}, publisher = {ELSEVIER SCI LTD}, address = {THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND}, abstract = {

The characteristic size, shape and specific alignment of magnetite crystals synthesized by magnetotactic bacteria is a highly coordinated process with precise control over magnetosome vesicle formation, uptake and transport of Fe, and magnetite biomineralization. Magnetosome membranes along with some specific membrane proteins regulate crystal nucleation and morphology of magnetite. Several previous works have indicated that the morphology of mature magnetite crystals is largely unaffected by environmental conditions, though some recent studies have shown the possibility of manipulation of the biomineralization process. In this study we have examined the effects of high concentrations of Zinc and Nickel on the growth of Magnetospirillum magnetotacticum (MS-1) and the corresponding magnetosome formation. Using various characterizations it is shown that the growth of the bacterial cells, as well as the size, shape and magnetosome chain alignment is significantly influenced in the presence of high concentrations of Zn or Ni. (C) 2009 Elsevier Ltd. All rights reserved.

}, keywords = {Biomineralization, magnetite, Magnetosome, Magnetospirillum magnetotacticum, Nickel, zinc}, issn = {0142-9612}, doi = {10.1016/j.biomaterials.2009.04.039}, author = {Kundu, S. and Kale, A. A. and Banpurkar, Arun G. and Kulkarni, G. R. and Ogale, S. B.} } @article { ISI:000288784400025, title = {Growth of aligned ZnO nanorods array on ITO for dye sensitized solar cell}, journal = {Current Applied Physics}, volume = {11}, number = {1, 1, SI}, year = {2011}, note = {International Conference on Electronic Materials (IUMRS-ICEM), Seoul, SOUTH KOREA, AUG 22-27, 2010}, month = {JAN}, pages = {S113-S116}, publisher = {Int Union Mat Res Soc (IUMRS)}, address = {PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS}, abstract = {

Aligned ZnO films of nanorods arrays were grown on Indium doped Tin oxide (ITO) glass substrate for the Dye Sensitized Solar Cells (DSSCs) applications. Two-step approach was employed for the deposition, which offers advantages such as excellent surface adhesion, large area deposition, high reproducibility and yield. Structural characterization using X-ray diffraction (XRD) shows a preferred c-axis (002) oriented growth. Scanning Electron Microscopy (SEM) images reveals uniformly distributed hexagonal ZnO nanorods with average diameter varying from 80 to 250 nm. Average growth rate of the films was estimated using Surface Profilometer which was found to be similar to 1 mu m/h. Optical characterizations were carried out using Photo-spectrometer and Raman spectroscopy. The DSSCs using these ZnO films of nanorods array as photo-electrodes show conversion efficiency ranging from 0.24 to -0.71 \%, the maximum efficiency was obtained for films deposited for time duration 8 h. (C) 2010 Elsevier B.V. All rights reserved.

}, keywords = {Aligned ZnO nanorod growth, Dye sensitized solar cell, Open aqueous solution deposition}, issn = {1567-1739}, doi = {10.1016/j.cap.2010.11.111}, author = {Yengantiwar, Ashish and Sharma, Ramakant and Game, Onkar S. and Banpurkar, Arun G.} } @article { ISI:000296659000032, title = {Strong photo-response in a flip-chip nanowire p-Cu2O/n-ZnO junction}, journal = {Nanoscale}, volume = {3}, number = {11}, year = {2011}, month = {OCT}, pages = {4706-4712}, publisher = {ROYAL SOC CHEMISTRY}, type = {Article}, address = {THOMAS GRAHAM HOUSE, SCIENCE PARK, MILTON RD, CAMBRIDGE CB4 0WF, CAMBS, ENGLAND}, abstract = {

Cu2O nanoneedles are synthesized on a copper substrate by a simple anodization and reducing ambient annealing protocol. ZnO nanorods are grown on ITO coated glass by a low temperature chemical route. The electronic and photo-response properties of the p-Cu2O/n-ZnO flip-chip heterojunction are then studied and analyzed. We show that the I-V characteristic is rectifying and the junction exhibits a good photoresponse (similar to 120\% under 1 V reverse bias) under AM 1.5 (1 Sun) illumination. This nano-heterojunction photo-response is far stronger as compared to that of a pulsed laser deposited thin film p-Cu2O/n-ZnO heterojunction, which can be attributed to higher junction area in the former case.

}, issn = {2040-3364}, doi = {10.1039/c1nr10665a}, author = {Deo, Meenal S. and Mujawar, Sarfraj and Game, Onkar S. and Yengantiwar, Ashish and Banpurkar, Arun G. and Kulkarni, Sneha and Jog, Jyoti Prakash and Ogale, Satishchandra B.} } @article { ISI:000302639600011, title = {Quantum dot bio-conjugate: as a western blot probe for highly sensitive detection of cellular proteins}, journal = {Journal of Nanoparticle Research}, volume = {14}, number = {3}, year = {2012}, month = {MAR}, pages = {732}, publisher = {SPRINGER}, address = {VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS}, abstract = {

In the present study, we report a quantum dot (QD)-tailored western blot analysis for a sensitive, rapid and flexible detection of the nuclear and cytoplasmic proteins. Highly luminescent CdTe and (CdTe) ZnS QDs are synthesized by aqueous method. High resolution transmission electron microscopy, Raman spectroscopy, fourier transform infrared spectroscopy, fluorescence spectroscopy and X-ray diffraction are used to characterize the properties of the quantum dots. The QDs are functionalized with antibodies of prostate apoptosis response-4 (Par-4), poly(ADP-ribose) polymerases and beta actin to specifically bind with the proteins localized in the nucleus and cytoplasm of the cells, respectively. The QD-conjugated antibodies are used to overcome the limitations of conventional western blot technique. The sensitivity and rapidity of protein detection in QD-based approach is very high, with detection limits up to 10 pg of protein. In addition, these labels provide the capability of enhanced identification and localization of marker proteins in intact cells by confocal laser scanning microscopy.

}, keywords = {Detection, Imaging, nanomedicine, quantum dot, Rapid, sensors, Western blot}, issn = {1388-0764}, doi = {10.1007/s11051-012-0732-9}, author = {Kale, Sonia and Kale, Anup and Gholap, Haribhau and Rana, Abhimanyu and Desai, Rama and Banpurkar, Arun G. and Ogale, Satishchandra and Shastry, Padma} } @article { ISI:000351551800013, title = {Hysteretic DC electrowetting by field-induced nano-structurations on polystyrene films}, journal = {Soft Matter}, volume = {11}, number = {13}, year = {2015}, month = {FEB}, pages = {2655-2664}, publisher = {ROYAL SOC CHEMISTRY}, address = {THOMAS GRAHAM HOUSE, SCIENCE PARK, MILTON RD, CAMBRIDGE CB4 0WF, CAMBS, ENGLAND}, abstract = {

Electrowetting (EW) offers executive wetting control of conductive liquids on several polymer surfaces. We report a peculiar electrowetting response for aqueous drops on a polystyrene (PS) dielectric surface in the presence of silicone oil. After the first direct current (DC) voltage cycle, the droplet failed to regain Young{\textquoteright}s angle, yielding contact angle hysteresis, which is close to a value found in ambient air. We conjecture that the hysteretic EW response appears from in situ surface modification using electric field induced water-ion contact with PS surface inducing nano-structuration by electro-hydrodynamic (EHD) instability. Atomic force microscopy confirms the formation of nano-structuration on the electrowetted surface. The effects of molecular weight, applied electric field, water conductivity and pH on nano-structuration are studied. Finally, the EW based nano-structuration on PS surface is used for the enhanced loading of aqueous dyes on hydrophobic surfaces.

}, issn = {1744-683X}, doi = {10.1039/c5sm00007f}, author = {Sawane, Yogesh B. and Datar, Suwarna and Ogale, Satishchandra B. and Banpurkar, Arun G.} } @article { ISI:000369515700086, title = {Solution chemistry-based nano-structuring of copper dendrites for efficient use in catalysis and superhydrophobic surfaces}, journal = {RSC Advances}, volume = {6}, number = {10}, year = {2016}, month = {JAN}, pages = {8416-8430}, publisher = {ROYAL SOC CHEMISTRY}, address = {THOMAS GRAHAM HOUSE, SCIENCE PARK, MILTON RD, CAMBRIDGE CB4 0WF, CAMBS, ENGLAND}, abstract = {

Despite their performance and economic advantages over Ag and Au, there have been no focused research efforts on the nano-structuring of Cu dendrites with respect to fine-tuning their structure/morphology towards the efficiency enhancement of suitable applications. Reported here is a simple, versatile, environmentally-friendly and galvanic replacement reaction-based solution chemistry methodology to synthesize highly nano-structured copper dendrites targeted towards the efficiency enhancement of desired applications. Herein, copper is deposited galvanically on an Al foil in the presence of NaCl/HCl, wherein the chloride anions augment an uninterrupted replacement reaction. The growth process of Cu dendrites has been probed in detail. The presence of acid, the type of Cu2+ precursor salt, the Cu2+ ion concentration, the surfactant concentration and the reaction temperature are all demonstrated to provide useful means of modulating the surface structure/morphology of the dendrites. Notably, dendrites formed in the presence of acid are found to be highly nano-structured. Moreover, it is also found that the morphology/structure of the obtained Cu deposit depends considerably upon the choice of the Cu2+ precursor salt, a parameter that has been completely overlooked in the past. The acid-induced nano-structuring of the dendrites is exploited for enhancing their efficiency in the catalytic reduction of para-nitrophenol and for fabricating self-cleaning superhydrophobic surfaces. These nano-structured dendrites are demonstrated to have the highest ever normalized rate constant for the catalytic reduction reaction. Superhydrophobic surfaces fabricated using these dendrites demonstrate excellent self-cleaning abilities, showing a high contact angle (159 degrees) with low contact angle hysteresis (2 degrees). This facile synthetic strategy for the fabrication of highly nano-structured Cu dendrites is expected to open up avenues for the production of Cu-based low-cost functional nano/micro-materials.

}, issn = {2046-2069}, doi = {10.1039/c5ra22683j}, author = {Bakthavatsalam, Rangarajan and Ghosh, Subrata and Biswas, Ratul Kumar and Saxena, Aayushi and Raja, Alagar and Thotiyl, Musthafa Ottakam and Wadhai, Sandip and Banpurkar, Arun G. and Kundu, Janardan} } @article {43849, title = {Facile synthesis and self-cleaning application of bimetallic (CuSn, CuNi) dendrites}, journal = {Chemistryselect}, volume = {2}, year = {2017}, month = {JUL}, pages = {5552-5563}, type = {Article}, abstract = {

Bimetallic dendrites (Au, Ag, Pt, Pd) have received intense research interest due to their applications in catalysis and sensing. However, reports on rational synthesis of non-noble bimetallic dendrites that finds self-cleaning applications are scanty. Here, we demonstrate one step co-reduction based galvanic replacement reaction (GRR) for synthesis of alloyed bimetallic dendrites (CuSn, CuNi) with controlled surface roughness and chemical composition. Probing their growth process reveals that i) for CuSn dendrites, co-reduction of Cu2+ and Sn2+ is observed throughout GRR; ii) for CuNi dendrites, Cu nanoparticle, that deposits initially, augments the reduction of Ni2+ which leads to CuNi alloy phase formation during later stages of GRR. These dendrites, naturally having dual degree of surface roughness (micro/nano), have been exploited here for fabricating superhydrophobic surfaces (SHS) with excellent self-cleaning abilities. They show enabling properties such as high contact angle, minimal contact angle hysteresis, and excellent Cassie state stability with no impalement. They maintain superhydrophobicity when exposed to different environmental conditions (low temperature, high temperature, exposure to corroding solutions and UV radiation). The present facile methodology for fabrication of bimetallic dendrites is beneficial for low-cost production of functional nano/micro-materials.

}, doi = {10.1002/slct.201700763}, author = {Biswas, Anupam and Kulkarni, Mayuresh A. and Bakthavatsalam, Rangarajan and Mondal, Sourik K. and Dwivedi, Pravin K. and Shelke, Manjusha V. and Devi, Radhamonyamma N. and Banpurkar, Arun G. and Kundu, Janardan} } @article {46307, title = {Novel fatty alkene from marine bacteria: a thermo stable biosurfactant and its applications}, journal = {Journal of Hazardous Materials}, volume = {380}, year = {2019}, month = {DEC}, pages = {UNSP 120868}, type = {Article}, abstract = {

In this study, a novel thermo stable biosurfactants, 1-Pentanonacontene (C95H190) a fatty alkene and 3-Hydroxy16-methylheptadecanoic acid (C18H36O3) were isolated from a marine isolate SGD-AC-13. Biosurfactants were produced using 1\% yeast extract in tap water as production medium at 24 h in flask and 12 h in bioreactor. Using 16S rRNA gene sequence (1515 bp) and BCL card (bioMerieux VITEK (R)), strain was identified as Bacillus sp. Crude biosurfactant reduced the surface tension of distilled water to 31.32 +/- 0.93 mN/m with CMC value of 0.3 mg/ml. Cell free supernatant showed excellent emulsification and oil displacement activity with stability up to 160 degrees C, pH 6-12 and 50 g/L NaCl conc. Biosurfactants were characterized using FTIR, TLC, HPLC LC-MS and NMR spectroscopy. Cell free supernatant reduced the contact angle of distilled water droplet from 117 degrees to 52.28 degrees and of 2\% pesticide from 78.77 degrees to 73.42 degrees while 750 mu g/ml of crude biosurfactant reduced from 66.06 degrees to 56.33 degrees for 2\% pesticide and recovered 35\% ULO and 12\% HWCO from the contaminated sand. To our best of knowledge, this is the first report of thermo stable fatty alkene as a biosurfactant and is structurally different from previously reported, with having potential application in agriculture, oil recovery and bioremediation.

}, keywords = {Bioremediation, Biosurfactants, Fatty alkene, Thermo stability, Wettability}, issn = {0304-3894}, doi = {10.1016/j.jhazmat.2019.120868}, author = {Ram, Hari and Sahu, Amit Kumar and Said, Madhukar S. and Banpurkar, Arun G. and Gajbhiye, Jayant M. and Dastager, Syed G.} }