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Biology subjects

Dhiman, T. K.

Publications and source records attributed to Dhiman, T. K..

2 recordsLinked to original sources

Optical tuning of polymer functionalized zinc oxide quantum dots as a selective probe for specific detection of antibiotics

It is crucial to monitor the antibiotic levels in the environment like water, food products in the current scenario as the antibiotic concentration above threshold is harmful for the human health. Excess consumption of antibiotics leads to antibiotic resistance that hinders the control and cure of microbial diseases. So, these challenges motivated to devise an optical nano-senor which can sense the ultra-low concentration of antibiotics. In this proposed research work, emphasis is to develop a method which is simple and selective to analyze the detection and presence of antibiotics in various samples like tape water milk etc. using fluorescent ZnO QDs based nano-sensor. For this, fluorescent and different polymers (polyvinylalcohol - PVA and polyvinylpyrrolidine - PVP) capped ZnO QDs were synthesized using modified sol-gel technique. These were used as fluorescent probe to monitor the presence of antibiotics. The optical characterizations of synthesized QDs were performed using UV-Visible absorption & fluorescence spectroscopic methods while structural characteristics were analyzed by using FTIR, XRD and EDX. Charge on the synthesized QDs were obtained with the help of ZETA potential. Here ten different antibiotics were targeted among, Ciprofloxacin and Moxifloxacin have shown excellent sensing and specificity with PVA-ZnO QDs and PVP-ZnO QDs respectively.

biophysics↗

Experimental and In Silico interaction studies of Alpha Amylase-Silver nanoparticle: a nano-bio-conjugate

In the current work, biosynthesis of silver nanoparticle (Ag NPs) and interaction study between alpha amylase and Ag NPs/nanocluster has been performed via wet-lab as well as in silico approach. We have synthesized Ag NPs using alpha amylase enzyme which reduces the silver nitrate precursor forming the stable Ag NPs. UV-Visible spectroscopy and fluorescence spectroscopies were performed for optical characterization of Ag NPs. UV-Vis spectra showed the wide absorption band centered around 475 nm due to surface plasmon resonance. We have also observed gradual decrease in fluorescence intensity with the increase in incubation time. Also, shift in {lambda}max of the emission spectra was recorded which clearly suggested the formation of nano-bio-conjugate. Circular dichroism spectra show the initial decrease in the ellipticity, when we added the silver nitrate, but after incubating for different time, there are no major changes in secondary structure of protein. In computational study we have modelled ground state configuration of (Ag)24 nanocluster using in silico approach. Further docking of the modelled optimized nanocluster with alpha amylase was performed and found that Ag-nanocluster showing non-covalent interaction with alpha amylase and forming stable docking complex.

biophysics↗