@article { ISI:000312472000040, title = {Gold nanoparticle embedded hydrogel matrices as catalysts: better dispersibility of nanoparticles in the gel matrix upon addition of N-bromosuccinimide leading to increased catalytic efficiency}, journal = {Colloids and Surfaces A-Physicochemical and Engineering Aspects}, volume = {414}, year = {2012}, month = {NOV}, pages = {296-301}, publisher = {ELSEVIER SCIENCE BV}, address = {PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS}, abstract = {

A simple and convenient method for generating and immobilizing gold NPs into polyethylene glycol-polyurethane (PEGPU) matrices is presented. The gold NP immobilized PEGPU (Au NP-PEGPU) hydrogel matrices are easy to handle and can be used as catalysts. The efficiency, reusability and durability of the Au NP-PEGPU catalyst matrices were investigated using the reduction of 4-nitroaniline (4NA) to p-phenylenediamine (p-PDA) by sodium borohydride in the presence of the catalyst as a test reaction. The Au NPs in the PEGPU matrix got aggregated after 3 cycles of catalysis but dispersion could be regenerated by the addition of N-bromosuccinimide (NBS). After this regeneration process the Au NPs-PEGPU matrix showed excellent efficiency without any aggregation, leaching or degradation. The reusability of the catalyst for 28 cycles yielding a total turnover number of 3220 and turn over frequency of 0.152 s(-1) is demonstrated. (C) 2012 Elsevier B.V. All rights reserved.

}, keywords = {catalysis, hydrogels, Immobilization, Nanoparticles, Turn over numbers}, issn = {0927-7757}, doi = {10.1016/j.colsurfa.2012.08.026}, author = {Ramtenki, Vilas and Anumon, V. D. and Badiger, Manohar V. and Bhagavatula L. V. Prasad} } @article { ISI:000325763700047, title = {Synthesis of Ag-glyconanoparticles using C-glycosides, their lectin binding studies and antibacterial activity}, journal = {New Journal of Chemistry}, volume = {37}, number = {11}, year = {2013}, month = {AUG}, pages = {3716-3720}, publisher = {ROYAL SOC CHEMISTRY}, address = {THOMAS GRAHAM HOUSE, SCIENCE PARK, MILTON RD, CAMBRIDGE CB4 0WF, CAMBS, ENGLAND}, abstract = {

Two 12-C-glycosyl dodecanoic acids, namely, 1-(alpha-D-mannopyranosyl)-12-dodecanoic acid and 1-(alpha-D-glucopyranosyl)-12-dodecanoic acid were synthesized. Their ability to act as reducing and capping agents for the synthesis of water re-dispersible silver nanoparticles is displayed. These Ag C-glycosyl nanoparticles were later utilized to investigate the carbohydrate-lectin interactions. Furthermore, the specificity of mannoside binding to the surface of the Gram negative bacterium Escherichia coli has been utilized to demonstrate the enhanced antibacterial activity of Ag-C-mannosyl nanoparticles towards this bacterium as compared to Ag-C-glycosyl nanoparticles.

}, issn = {1144-0546}, doi = {10.1039/c3nj00496a}, author = {Ramtenki, Vilas and Raju, D. and Mehta, Urmil J. and Ramana, C. V. and Bhagavatula L. V. Prasad} } @article {49484, title = {Design and synthesis of C-α-D-mannopyranoside linked mesoporous silica nanoparticles}, journal = {Journal of Chemical Sciences}, volume = {137}, year = {2025}, month = {MAR }, pages = {21}, type = {Article}, abstract = {

Mannose functionalized mesoporous silica nanoparticles (MSNs) offer a promising approach for developing more targeted, effective, and safer cancer therapies. For many of the applications, immobilization of carbohydrates like mannose onto MSNs is a crucial aspect, and in most cases, mannose moieties are connected through O-glycosidic linkages that are susceptible to acidic/enzymatic hydrolysis. To generate a stable mannose-functionalized MSN, we designed a novel C(14)-alpha-mannosylated tetradeca-1-yne. The key steps involved in the synthesis of C-mannosylated alkyne are C1-alkynylation of tri-O-acetyl-D-glucal with 1-trimethylsilyl-tetradec-1-yne, followed by stereoselective dihydroxylation and the isomerization of the internal triple bond to a terminal position. This mannose ligand was then immobilized onto azidopropyl-functionalized SBA-15 through the Cu(I)-catalyzed azide-alkyne click (CuAAC) reaction. Various physical techniques such as low-angle powder XRD, N-2 adsorption isotherms (BET), Fourier transform infrared (FTIR), high-resolution transmission electron microscopy (HRTEM), field emission scanning electron microscopy (FE-SEM), and thermogravimetric analysis (TGA) have been employed to characterize this C-mannosyl SBA-15 silica matrix. We evaluated the binding ability of C-mannosyl SBA-15 nanoparticles by using fluorescein-labelled Con-A as a target protein.

}, keywords = {C-mannoside, Click reaction, mannose specific proteins, Mesoporous silica nanoparticles, Zipper reaction}, issn = {0974-3626}, doi = {10.1007/s12039-024-02338-7}, author = {Nechooli, Hemanth K. and Ramtenki, Vilas and Kumar, Chepuri V. Suneel and Prasad, V. B. L. and Ramana, V. Chepuri} }