Vinayak A. Dhumale

Curcumin Conjugated Silica Nanoparticles for Improving Bioavailability and Its Anticancer Applications

Curcumin, a yellow bioactive component of Indian spice turmeric, is known to have a wide spectrum of biological applications. In spite of various astounding therapeutic properties, it lacks in bioavailability mainly due to its poor solubility in water. In this work, we have conjugated curcumin with silica nanoparticles to improve its aqueous solubility and hence to make it more bioavailable. Conjugation and loading of curcumin with silica nanoparticles was further examined with transmission electron microscope (TEM) and thermogravimetric analyzer. Cytotoxicity analysis of synthesized silica:curcumin conjugate was studied against HeLa cell lines as well as normal fibroblast cell lines. This study shows that silica:curcumin conjugate has great potential for anticancer application.

Antimicrobial potential of TiO2 nanoparticles against MDR Pseudomonas aeruginosa

The present study aims to evaluate the inhibition effectiveness of titanium dioxide nanoparticles in combination with cell wall active antibiotics – ceftazidime and cefotaxime against the multi-drug resistant Pseudomonas aeroginosa isolated from pus, sputum, endo-tracheal tract and broncho-alveolar lavage. Commercial Degussa-P25 TiO2 nanoparticle, antibiotics ceftazidime and cefotaxime were used in this study against multi-drug-resistant nosocomial pathogen. The nanoparticle shows antimicrobial effect on the pathogen at concentrations more than 350 μg/mL, when exposed to ultraviolet (UV) light for an hour. Minimum inhibitory concentration values obtained for the antibiotic cefotaxime were sixfolds higher than the antibiotic ceftazidime. When these antibiotics were used in combination with UV-irradiated metal nanoparticle, ceftazidime resulted in enhanced antimicrobial activity whereas cefotaxime does not show any change.

Decoration of gold nanoparticles on thin multiwall carbon nanotubes and their use as a glucose sensor

Thin multiwall carbon nanotubes (MWCNTs) have been decorated with gold nanoparticles (Au NPs) with polyaniline (PANI) as an inter-linker by a simple wet chemical method. The synthesized AuNPs:MWCNT:PANI composite was studied with UV–vis, FTIR, Raman spectroscopy, x-ray diffractometer, transmission electron microscopy (TEM) and atomic force microscopy (AFM). Conducting AFM (C-AFM) images of the composite reveal the role played by the two components in electrochemical reactions. The size of the Au NPs was found to be 13 ± 2 nm in the composite as observed from TEM. The synthesized AuNPs:MWCNT:PANI composite was further drop casted onto a glassy carbon electrode (GCE) for electrocatalytic study. The resulting composite exhibits good electrocatalytic activity towards reduction of H2O2 and O2. A glucose biosensor was developed by immobilizing glucose oxidase into AuNPs:MWCNT:PANI composite film on GCE. The fabricated sensor demonstrates good linear response to glucose (i.e. R = 0.9975) in the range of 2 to 12 mM.

Gold-graphene nanocomposite based ultrasensitive electrochemical glucose sensor

Gold-graphene (Au-G) nanocomposite has been synthesized by wet chemical method. Synthesized Au-G nanocomposite was examined under the UV-vis spectroscopy and transmission electron microscopy (TEM). Further Au-G nanocomposite was drop casted onto the glassy carbon electrode (GCE) by immobilizing glucose oxidase (GOx) into it for the electrochemical detection of glucose. Fabricated sensor demonstrates good linear response to glucose in the range 3 to 18 mM with linearity coefficient 0.964.