Interaction of an Antituberculosis Drug with Nano‐sized Cationic Micelle: Förster Resonance Energy Transfer from Dansyl to Rifampicin in the Microenvironment

Abstract

In this contribution, we report studies on the interaction of an antituberculosis drug rifampicin (RF) in a macromolecular assembly of CTAB with an extrinsic fluorescent probe, dansyl chloride (DC). The absorption spectrum of the drug RF has been employed to study Förster resonance energy transfer (FRET) from DC, bound to the CTAB micelle using picosecond resolved fluorescence spectroscopy. We have applied a kinetic model developed by Tachiya to understand the kinetics of energy transfer and the distribution of acceptor (RF) molecules around the donor (DC) molecules in the micellar surface with increasing quencher concentration. The mean number of RF molecules associated with the micelle increases from 0.24 at 20 μm RF concentration to 1.5 at 190 μm RF concentration and consequently the quenching rate constant (k(q)) due to the acceptor (RF) molecules increases from 0.23 to 0.75 ns(-1) at 20 and 190 μm RF concentration, respectively. However, the mean number of the quencher molecule and the quenching rate constant does not change significantly beyond a certain RF concentration (150 μm), which is consistent with the results obtained from time resolved FRET analysis. Moreover, we have explored the diffusion controlled FRET between DC and RF, using microfluidics setup, which reveals that the reaction pathway follows one-step process.

Ultrafast interfacial solvation dynamics in specific protein DNA recognition

“…The observation corroborates the findings of the CD study, which also indicates the structural changes within O R 2 DNA. For better understanding of the energy transfer from the excited state of H258 to EtBr molecules, it is imperative to know the distribution of acceptor (EtBr) molecules within the DNA, as it is a governing factor that can influence the energy transfer rate as observed from the time resolved fluorescence studies [43]. In this context, we have applied a kinetic model developed by Tachiya [44] for the quenching of luminescent probes undergoing non-radiative energy transfer in restricted environments.…”

Nanoscale Ultrasound‐Switchable FRET‐Based Liposomes for Near‐Infrared Fluorescence Imaging in Optically Turbid Media

“…For example, FRET and SQ are dependent on the intermolecular distances of fluorophores and they are also diffusion controlled processes . Figure demonstrates that US can either increase or decrease the fluorescence depending on fluorophore concentration.…”

Nano-MOFs as targeted drug delivery agents to combat antibiotic-resistant bacterial infections

“…In this work, we have used rifampicin (RF), a compelling antituberculosis drug that has tremendous pharmacological significance [28]. The common antimicrobial RF covers a wide scope of natural action while these investigations propose the use of ZIF8 frameworks for focused targeted drug delivery operators to combat antimicrobial resistance bacterial infections.…”