A fluorescence study on the interaction of telmisartan in triblock polymers pluronic P123 and F127

A Fluorescence Study of the Interaction of Anticancer Drug Molecule Doxorubicin Hydrochloride in Pluronic P123 and F127 Micelles

Drug delivery systems for the sustained and target delivery of doxorubicin to tumor cells are a topic of interest due to the efficacy of the doxorubicin in cancer treatment. The use of polymers such as Pluronic is being studied widely for the formulation of doxorubicin hydrochloride. However, the basic understanding of the physicochemical properties of pluronic micelles in presence of doxorubicin hydrochloride is a very essential topic of study. Doxorubicin hydrochloride is fluorescent; this helped us to study its sensitivity towards the Pluronic microenvironment using the fluorescence technique. In this work, the interaction and place of location of doxorubicin hydrochloride in Pluronic F127 and P123 micelles has been studied extensively using steady-state fluorescence intensity, dynamic fluorescence lifetime, quenching studies, dynamic light scattering, and zeta potential measurements, at different Pluronic concentrations. Using a fluorescence quenching experiment, doxorubicin hydrochloride was found to reside near the hydrophilic PEO corona region of the Pluronic micelles. For both the Pluronic, in the concentration range of study, the micellar size was found to be below 30 nm; this may have a greater advantage for various applications.

Nile red fluorescence for quantitative monitoring of micropolarity and microviscosity of pluronic F127 in aqueous media

The photophysical behaviour and excited state decay kinetics of the fluorescent probe Nile red were used for quantitative monitoring of micropolarity, microviscosity and the sol-gel transition temperature of a copolymer hydrogel, pluronic F127. There was considerable enhancement of the emission intensity with a large blue shift in emission and an absorption maximum at and above the sol-gel transition temperature (20 °C), showing the sensitivity of Nile red fluorescence to the sol-gel transition. The estimation of micropolarity by comparing the Nile red emission maximum in dioxane-water mixtures suggested a considerable decrease in the polarity of the PF127 microenvironment from less polar (20% dioxane-water) in its sol phase to almost non-polar (90% dioxane-water) microenvironments in the gel phase. The thermotropic response of the wavelength dependent fluorescence lifetime of the probe with a rise time in the longer wavelength region has enabled monitoring of the microheterogeneity of the gel medium. With an increase in temperature, the microviscosity progressively increases from ∼10 mPa s (sol state) to ∼23 mPa s (gel state). The mismatch between microviscosity as estimated by the Nile red and the corresponding bulk viscosity reflected the microheterogeneity of the pluronic medium and its sensitivity towards PF127 microenvironments.

Recent progress in drug delivery of pluronic P123: pharmaceutical perspectives

This review focuses on recent investigations that used Pluronic P123 (P123) as pharmaceutical ingredients in vesicle, micelle, mixed micelle, in situ gel, tablet and emulsion. The main results from these studies show that P123 can significantly increase the stability of incorporated hydrophobic drugs with enhanced in vitro cytotoxicity and cellular uptake of anticancer drugs. Moreover, modified forms of P123 with RGD, folate or other targeted marker have shown its therapeutic potentials in various types of tumors and cancers. Furthermore, modified forms of P123 alone and/or mixed with other copolymers have less toxic effects and more tumor-specific delivery of anticancer drugs. They are promising materials as a nanoplatform for the drug delivery. Finally, the future perspectives of the field are briefly discussed.

Study on binding and fluorescence energy transfer efficiency of Rhodamine B with Pluronic F127-gold nanohybrid using optical spectroscopy methods

This work focuses on the binding efficiency and fluorescence resonance energy transfer (FRET) of fluorescent dye Rhodamine B (Rh B) to Pluronic F127-gold nanohybrid. The formation of gold nanoparticles inside Rh B doped Pluronic F127 copolymer have been characterized using dynamic light scattering study, HR-TEM images, UV-visible spectra and fluorescence studies. Fluorescence quenching and the constant fluorescence lifetime of the Rhodamine B present in the cavity of Pluronic F127-gold nanohybrid suggested a strong binding ability (3.5×10³Lmol^-1), static nature of quenching and better energy transfer efficiency of fluorescent dye towards Pluronic F127-gold (Au) nanohybrids.

Introduction of an α,β-unsaturated carbonyl conjugated pyrene–lactose hybrid as a fluorescent molecular probe for micro-scale anisotropic media

A new fluorescent lactose molecule (pyd-lact) (E)-1-(galactose-β-(1→4)-β-d-glucopyranosyl)-4-(1-pyrene)-but-3-en-2-one, has been synthesized by attaching 1-pyrene-but-3-ene-2-one to lactose.

Monitoring thermo-reversible dehydration of the pluronic microenvironment using 4-chloro-1-naphthol as an ESPT fluorescent molecular probe

An ESPT fluorescent molecular probe, 4-chloro-1-naphthol, has been employed to study the thermo-reversible sol–gel transition, dehydration and micro-polarity of pluronics.

Utilizing an aggregate forming microenvironment sensitive coumarin–cholesterol conjugate as a sensor of pluronic organization and micro-polarity

A new fluorescent cholesterol molecular probe, 3-acetyl-7-(diethylamino)-2H-chromen-2-one attached cholesterol (Cum–Chl), has recently been introduced as a reporter of micro-heterogeneous media.

1-Naphthol as an ESPT fluorescent molecular probe for sensing thermotropic microenvironmental changes of pluronic F127 in aqueous media

Thermotropic microenvironmental changes and the level of hydration in different microenvironments of pluronic F127 (PF127), (PEO₁₀₆ PPO₇₀ PEO₁₀₆, average molar mass 13 000) in aqueous media have been studied using 1-naphthol, which is an ESPT fluorescent molecular probe.