@article { ISI:000287277700038, title = {Quantum dot based immunosensor using 3D circular microchannels fabricated in PDMS}, journal = {Biosensors \& Bioelectronics}, volume = {26}, number = {6}, year = {2011}, month = {FEB}, pages = {3050-3053}, publisher = {ELSEVIER ADVANCED TECHNOLOGY}, type = {Article}, address = {OXFORD FULFILLMENT CENTRE THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND}, abstract = {

Microchannel is basic functional component of microfluidic chip and every step-forward of its construction technique has been receiving concern all over the world. The present work describes a novel, rapid and simple fabrication technique for building 3D microchannels in poly(dimethyl siloxane) (PDMS) elastomer. These microchannels were used for rapid detection of antigens (E. coli) by quantum dot (QD) based approach. Luminescent QD (CdTe) were synthesized by aqueous method and characterized using high resolution transmission electron microscopy (HRTEM), fluorescence spectroscopy and X-ray diffraction (XRD). The QDs were functionalized with anti-E. coli antibodies for immuno-detection. The reported process allowed easier and faster method of fabrication of circular 3D micochannels and demonstrated their potential use in an immuno-biosensor device. (C) 2010 Elsevier B.V. All rights reserved.

}, keywords = {Capillary driven flows, Circular microfluidics, Immunosensor, QDs}, issn = {0956-5663}, doi = {10.1016/j.bios.2010.12.017}, author = {Morarka, Amit and Agrawal, Shailaja and Kale, Sonia and Kale, Anup and Ogale, Satishchandra B. and Paknikar, Kishore and Bodas, Dhananjay S.} } @article { ISI:000327071100001, title = {Hollow nanogold/meso-magnetite composite: pulsed laser synthesis, properties, and biosensing application}, journal = {Journal of Nanoparticle Research}, volume = {15}, number = {12}, year = {2013}, month = {NOV}, pages = {Article No. UNSP 2081}, publisher = {SPRINGER}, type = {Article}, address = {VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS}, abstract = {

A facile and template-free UV (Excimer) laser photolysis process is demonstrated to transform a Fe-complex into unique hollow Fe3O4 nanosphere morphology with each sphere having nanometric pores and an opening. Depending on the Fe-complex concentration and processing time interesting configurations are seen to evolve. When an identical process is applied to a mixture of Fe-complex and chloroauric acid an enthrallingly decorated Au-Fe3O4 nanostructure evolves, with Au nanoparticles surface-loaded on mesospheric Fe3O4. This room temperature process implemented under normal laboratory conditions is clearly versatile and applicable to heterojunction nanomaterials synthesis in a single-step process. The potential application of these gold-decorated magnetic nanostructures was also investigated for immuno-magnetic capture of E. coli in biosensing and these were found to be sensitive even below 1,000 cfu/ml. The test results demonstrate linear sensing response in the range of 10(3)-10(5) cfu/ml. We also show that these nanostructures can be used for simple electrical conductivity-based biosensing since they show dramatic conductivity change in a simple drop-cast test. A new laser-based approach to the synthesis of unique hollow sphere morphology of magnetite (Fe3O4) without and with Au nanoparticle decoration is presented. The potential application of these gold-decorated magnetic nanostructures was also investigated for immuno-magnetic capture of E. coli in biosensing and these were found to be sensitive even below 1,000 cfu/ml.

}, keywords = {E. coli cells, Fe-complex, Meso-magnetite, Nanobiotechnology, Nanocomposite, Pulse laser irradiation}, issn = {1388-0764}, doi = {10.1007/s11051-013-2081-8}, author = {Chaudhari, Nilima and Warule, Sambhaji and Agrawal, Shailaja and Thakare, Vishal and Jouen, Samuel and Hannoyer, Beatrice and Kale, Bharat and Paknikar, Kishore and Ogale, Satishchandra B.} } @article {45934, title = {Fluorescent cadmium telluride quantum dots embedded chitosan nanoparticles: a stable, biocompatible preparation for bio-imaging}, journal = {Journal of Biomaterials Science-Polymer Edition}, volume = {26}, year = {2015}, month = {JAN }, pages = {42-56}, type = {Article}, abstract = {

Fluorescent cadmium telluride quantum dots (CdTe QDs) are an optically attractive option for bioimaging, but are known to display high cytotoxicity. Nanoparticles synthesized from chitosan, a natural biopolymer of beta 1-4 linked glucosamine, display good biocompatibility and cellular uptake. A facile, green synthetic strategy has been developed to embed green fluorescent cadmium telluride quantum dots (CdTe QDs) in biocompatible CNPs to obtain a safer preparation than {\textquoteleft}as is{\textquoteright} QDs. High-resolution transmission electron microscopy showed the crystal lattice corresponding to CdTe QDs embedded in CNPs while thermogravimetry confirmed their polymeric composition. Electrostatic interactions between thiol-capped QDs (4nm, -57mV) and CNPs (\~300nm, +38mV) generated CdTe QDs-embedded CNPs that were stable up to three months. Further, viability of NIH3T3 mouse fibroblast cells in vitro increased in presence of QDs-embedded CNPs as compared to bare QDs. At the highest concentration (10 mu g/ml), the former shows 34 and 39\% increase in viability at 24 and 48h, respectively, as compared to the latter. This shows that chitosan nanoparticles do not release the QDs up to 48h and do not cause extended toxicity. Furthermore, hydrolytic enzymes such as lysozyme and chitinase did not degrade chitosan nanoparticles. Moreover, QDs-embedded CNPs show enhanced internalization in NIH3T3 cells as compared to bare QDs. This method offers ease of synthesis and handling of stable, luminescent, biocompatible CdTe QDs-embedded CNPs with a favorable toxicity profile and better cellular uptake with potential for bioimaging and targeted detection of cellular components.

}, keywords = {Biocompatible, bioimaging, CdTe quantum dots, chitosan nanoparticles, Toxicity}, issn = {0920-5063}, doi = {10.1080/09205063.2014.982240}, author = {Ghormade, Vandana and Gholap, Haribhau and Kale, Sonia and Kulkarni, Vaishnavi and Bhat, Suresh and Paknikar, Kishore} } @article {43601, title = {Radio-frequency triggered heating and drug release using doxorubicin-loaded LSMO nanoparticles for bimodal treatment of breast cancer}, journal = {Colloids and Surfaces B-Biointerfaces}, volume = {145}, year = {2016}, month = {SEP}, pages = {878-890}, abstract = {Radio-frequency responsive nanomaterials combined with drugs for simultaneous hyperthermia and drug delivery are potential anti-cancer agents. In this study, chitosan coated La0.7Sr0.3MnO3 nanoparticles (C-LSMO NPs) were synthesized and characterized by X-ray diffraction, dynamic light scattering, Fourier transform infra red spectroscopy, vibrating sample magnetometer, scanning electron and atomic force microscopy, Under low radio-frequency (365 kHz, RF), C-LSMO NPs (90 nm) showed good colloidal stability (+22 mV), superparamagnetic nature (15.4 emu/g) and heating capacity (57.4W/g SAR value). Chitosan facilitated doxorubicin entrapment (76\%) resulted in DC-LSMO NPs that showed drug release upon a 5 min RF exposure. MCF-7 and MDA-MB-231 cancer cells responded to a 5 min RF exposure in the presence of bimodal DC-LSMO NPs with a significant decrease in viability to 73\% and 88\% (Pearson correlation, r = 1, P<0.01) respectively, as compared to hyperthermia alone. Internalization of DC-LSMO NPs via the endosomal pathway led to an efficient localization of doxorubicin within the cell nucleus. The ensuing DNA damage, heat shock protein induction, and caspase production triggered apoptotic cell death. Moreover, DC-LSMO NPs successfully restricted the migration of metastatic MDA-MB-231 cancer cells. These data suggest that DC-LSMO NPs are potential bimodal therapeutic agents for cancer treatment and hold promise against disease recurrence and drug resistance. (C) 2016 Elsevier B.V. All rights reserved.}, doi = {10.1016/j.colsurfb.2016.06.010}, author = {Kulkarni, Vaishnavi M. and Bodas, Dhananjay and Dhoble, Deepa and Ghormade, Vandana and Paknikar, Kishore} } @article {46254, title = { Development of a nano-gold immunodiagnostic assay for rapid on-site detection of invasive aspergillosis }, journal = {Journal of Medical Microbiology}, volume = {68}, year = {2019}, month = {SEP}, pages = {1341-1352}, type = {Article}, abstract = {

Introduction. Timely detection of invasive aspergillosis (IA) caused by fungal pathogens, i.e. Aspergillus fumigatus and Aspergillus flavus, in immunocompromised patients is crucial in preventing high mortality.

Aim. To develop a simple immunoassay for the detection of galactomannan (GM), an IA biomarker.

Methodology. GM from A. fumigatus and A. flavus clinical strains was purified and characterized by X-ray diffraction, IR spectroscopy and C-13/H-1 nuclear magnetic resonance (NMR) for polyclonal antibody (pAb) production in rabbits. An enzyme-linked immunosorbent assay (ELISA) was standardized using concanavalin A to capture Aspergillus GM and pAbs to detect it. Gold nanoparticles (AuNPs) were synthesized and conjugated to pAbs for the development of a dot-blot immunoassay. The developed dot-blot was evaluated with 109 clinical serum and bronchoalveolar lavage samples.

Results. Spectroscopy studies characterized the D-galactofuranosyl groups of GM responsible for the immune response and generation of pAbs. The ELISA employing pAbs showed a sensitivity of 1 ng ml(-1) for Aspergillus GM. Furthermore, a sensitive, visual, rapid dot-blot assay developed by the conjugation of pAbs to AuNPs (similar to 24 +/- 5 nm size, -36 +/- 2 mV zeta potential) had a detection limit of 1 pg ml(-1) in serum. The pAbs interacted with Aspergillus spp. but did not cross-react with other fungal pathogen genera such as Penicillium and Candida. Evaluation of the dot-blot with 109 clinical samples showed high sensitivity (80\%) and specificity (93.2 \%), with an overall assay accuracy of 89\%.

Conclusion. The developed nano-gold immunodiagnostic assay has immense potential for practical use in rapid, specific and sensitive on-site diagnosis of IA, even under resource-limited settings.

}, doi = {10.1099/jmm.0.001040}, author = {Raval, Komal M. and Ghormade, Vandana and Rajamohanan, P. R. and Choudhary, Hansraj and Rudramurthy, Shivaprakash M. and Chakrabarti, Arunaloke and Paknikar, Kishore} }