Effect of temperature on fluorescence quenching and emission characteristics of laser dyes

Abstract

Effect of temperature on fluorescence quenching and emission characteristics of laser dyes (LD – 473) and (LD – 423) have been investigated in the temperature range 25°C - 65°C by steady state and transient methods. The fluorescence intensity of both dyes is quenched in the presence of quencher aniline at different temperatures. Stern-Volmer (S-V) plots are non-linear showing positive deviation. It has been found that dynamic quenching constant increases with temperature, whereas static quenching constant is independent of temperature. In both the dyes, Fluorescence emission intensity has decreased with increase in temperature and fluorescence band maxima is slightly shifted towards shorter wavelength. Further, fluorescence lifetime has decreased with increase in temperature for both the dyes. The possible deactivation mechanisms are discussed.

Crystal Packing-Driven Selective Hg(II) Ion Sensing Using Thiazolothiazole-Based Water-Stable Zinc Metal–Organic Framework

“…The concentration-dependent emission quenching was estimated from the Stern–Volmer (SV) plot, which rendered the SV constant of 4.2 × 10 4 M –1 (at 40 °C) and 5.5 × 10 4 M –1 (at 50 °C) with a linear fit ( R 2 = 0.955 and 0.950, respectively). The similar value of the SV constant at different temperatures further fortified the static quenching mechanism (Figure S27).…”

The impact of nano-polystyrene on human serum albumin–paracetamol interactions: understanding the impact on therapeutic development and safety

“…The increase in K sv with the rise in temperature is a typical change observed in dynamic quenching (collision quenching). 29 The quenching rate constant ( K q ) was also observed to increase with an increase in temperature. The increase in K sv and K q with an increase in temperature suggests a reduction in activation energy for the protein–paracetamol interaction.…”

Divergent Synthesis of Ultrabright and Dendritic Xanthenes for Enhanced Click‐Chemistry‐Based Bioimaging

“…Previous work has demonstrated aggregates tend to diminish upon temperature elevation due to changes in the dynamic equilibrium, and thus resulting in an increase of fluorescence intensity.−– [45−–47] Conversely, non‐radiative rate constants and collisional quenching also tend to be amplified upon heating, leading to a decrease of fluorescence. [48] In order to evaluate which of the two effects predominate in our dendritic fluorophores, the fluorescence of these molecules was measured at varying temperature values between 25 °C and 65 °C, as shown in Figure 4 . In the event, the fluorescein‐based dendrons FD2 and FD4 exhibited comparable fluorescence decay behavior.…”

“…[45À -47] Conversely, non-radiative rate constants and collisional quenching also tend to be amplified upon heating, leading to a decrease of fluorescence. [48] In order to evaluate which of the two effects predominate in our dendritic fluorophores, the fluorescence of these molecules was measured at varying temperature values between 25 °C and 65 °C, as shown in Figure 4. In the event, the fluorescein-based dendrons FD2 and FD4 exhibited comparable fluorescence decay behavior.…”