arXiv subjects

Dibyendu Dey

Publications and source records attributed to Dibyendu Dey.

24 records · Page 2Linked to original sources

arXiv2014

Sensing of DNA conformation based on change in FRET efficiency between laser dyes

This communication reports the effect of DNA conformation on fluorescence resonance energy transfer (FRET) efficiency between two laser dyes in layer by layer (LbL) self assembled film. The dyes Acraflavine and Rhodamine B were attached onto the negative phosphate backbones of DNA in LbL film through electrostatic attraction. Then FRET between these dyes was investigated. Increase in pH or temperature causes the denaturation of DNA followed by coil formation of single stranded DNA. As a result the FRET efficiency also changed along with it. These observations demonstrated that by observing the change in FRET efficiency between two laser dyes in presence of DNA it is possible to detect the altered DNA conformation in the changed environment.

cond-mat.mtrl-sci↗

arXiv2014

Effect of nanoclay laponite and pH on the energy transfer between fluorescent dyes

Fluorescence resonance energy transfer (FRET) between two dyes acriflavine (Acf) and rhodamine B (RhB) were investigated in solution and Layer-by-Layer (LbL) self assembled films in presence and absence of clay mineral laponite. UV-Vis absorption and fluorescence spectroscopy studies suggest both the dyes present mainly as monomer in solution and films. Energy transfer occurred from Acf to RhB in solution and LbL films. The energy transfer efficiency increases in presence of clay laponite and the maximum efficiency were 78.17% and 32.54% in clay dispersion and in LbL films respectively. Presence of laponite particles onto LbL film was confirmed by atomic force microscopy investigations with a surface coverage of more than 75%. Energy transfer efficiency was pH sensitive and the energy transfer efficiency varies from 4.5% to 44.45% in mixed dye solution for a change in pH from 3.0 to 12.0. With proper calibration it is possible to use the present system under investigation to sense pH over a wide range of pH from 3.0 to 12.0.

cond-mat.mtrl-sci↗

arXiv2014

Development of hard water sensor using Fluorescence Resonance Energy Transfer

A method is presented for the sensing of water hardness by determining the concentration of calcium and magnesium in water, based on Fluorescence resonance energy transfer (FRET) process. The principle of the proposed sensor is based on the change of FRET efficiency between two laser dyes Acriflavine (Acf) and Rhodamine B (RhB) in presence of permanent hard water components (CaCl2 and MgCl2). Nanodimensional clay platelet laponite was used to enhance the efficiency of the sensor.

cond-mat.mtrl-sci↗

arXiv2014

Fluorescence Resonance Energy Transfer (FRET) sensor

The applications of Fluorescence resonance energy transfer (FRET) have expanded tremendously in the last 25 years, and the technique has become a staple technique in many biological and biophysical fields. FRET can be used as spectroscopic ruler in various areas such as structural elucidation of biological molecules and their interactions, in vitro assays, in vivo monitoring in cellular research, nucleic acid analysis, signal transduction, light harvesting, and metallic nanomaterials etc. Based on the mechanism of FRET a variety of novel chemical sensors and Biosensors have been developed. This review highlights the recent applications of sensitive and selective ratiometric FRET based sensors.

physics.bio-ph↗

arXiv2014

Development of a DNA sensor using molecular logic gate

This communication reports the increase in fluorescence resonance energy transfer (FRET) efficiency between two laser dyes in presence of Deoxyribonucleic acid (DNA). Two types of molecular logic gates have been designed where DNA acts as input signal and fluorescence intensity of different bands are taken as output signal. Use of these logic gates as DNA sensor has been demonstrated

physics.bio-ph↗

arXiv2014

Development of an Ion-Sensor using Fluorescence Resonance Energy Transfer

A method is presented for the sensing of ions by determining the concentration of corresponding salts (KCl, NaCl, MgCl2, CaCl2, FeCl3, FeSO4, AlCl3) in water, based on Fluorescence resonance energy transfer (FRET) process. The principle of the proposed sensor is based on the change of FRET efficiency between two laser dyes Acriflavine and Rhodamine B in presence of different ions (K+, Na+, Mg2+, Ca2+, Fe2+, Fe3+, Al3+). Nanodimensional clay platelet laponite was used to enhance the efficiency of the sensor.

cond-mat.mtrl-sci↗