What is Stern-Volmer constant?
What is Stern-Volmer constant?
The Stern–Volmer relationship, named after Otto Stern and Max Volmer, allows the kinetics of a photophysical intermolecular deactivation process to be explored. where A is one chemical species, Q is another (known as a quencher) and * designates an excited state.
How is Stern-Volmer constant calculated?
Saw your data points, they look beautiful. Now you calculate log(F0)/log(F). Plot this, take its slope, this is the Stern-Volmer constant.
What is the quenching constant?
Fluorescence Spectroscopy K is the Stern–Volmer quenching constant, [Q] is the molar concentration of quencher, and f is the fraction of accessible fluorophore to a polar quencher, which indicates the fractional fluorescence contribution of the total emission for an interaction with a hydrophobic quencher.
How do you find the quenching constant?
Plot the ln of intensity versus time and from the slope determine (kf + knr). Once (kf + knr) is determined, the value of the quenching rate constant can be determined from the Stern-Volmer plot.
How do you calculate quenching efficiency?
Quenching efficiency was determined by dividing the fluorescence intensity of the hybrid by the fluorescence intensity of the fluorophore-labeled oligodeoxyribonucleotide, multiplying the result by 100 and then subtracting the result from 100.
What is the slope of a Stern Volmer plot?
1 Answer. The slope of the Stern-Volmer plot is the Stern-Volmer constant Ksv, which is product of the quenching rate constant and the radiative life-time, i.e., Ksv = Kq . t0 where, Ksv = Stern Volmer constant, Kq = quenching rate constant, t0 = radiative life-time.
What is the value of the Y intercept of the Stern-Volmer plot?
The y-axis is the ratio of the unquenched fluorescence intensity divided by the quenched fluorescence intensity. The x-axis is the quencher concentration. The y-intercept is 1. The slope is the Stern-Volmer constant.
How is fluorescence quenching used in analytical measurements?
The Förster mechanism of fluorescence quenching can be used to infer the distance between donor and acceptor molecules, depending on the intensity of quenching. This determines the size or conformation of a protein and detects any interaction between proteins.
What is KSV in Stern-Volmer?
macromolecule; Ksv is the Stern–Volmer quenching constant; [Q] is the concentration. of quencher; τ0 is the average lifetime of the molecule without any quencher and the.
What are the application of Stern-Volmer equation?
Application of the Stern–Volmer equation for studying the spectrofluorimetric quenching reaction of eosin with clindamycin hydrochloride in its pure form and pharmaceutical preparations.
What is the Stern-Volmer equation for fluorescence quenching?
The Stern-Volmer equation in fluorescence quenching is straightforward derived assuming the following processes involving the fluorophore or probe in the excited state F* surrounded by quenchers Q in a bimolecular deactivation process, (3) F * → k 0 = 1 / τ 0 F + h ν F (4) F * + Q → k q F + Q
What is the Stern-Volmer mechanism?
The quenching constant is a comparison of the rate of quenching and the rate of formation of the first excited state. The intercept is expected to be one to within experimental error. This process is called the Stern- Volmer mechanism. 3 Figure 1: Stern-Volmer plot for fluorescence quenching.
How to calculate KQ in Stern Volmer relation?
You can see that also Stern Volmer relation is a linear function (of concentration). Thus, kq can be calculated by equating value of slope you obtained ( a) to kq / klum. Such procedure is simple and important to understand as can be used to determine many quantities which occur in linear equations.
What is the quenching constant and the intercept?
The quenching constant is a comparison of the rate of quenching and the rate of formation of the first excited state. The intercept is expected to be one to within experimental error. This process is called the Stern- Volmer mechanism.
