What is fluorescence with example?
Fluorescence is the emission of light by a substance that has absorbed light or other electromagnetic radiation. It is a form of luminescence. Fluorescent materials cease to glow nearly immediately when the radiation source stops, unlike phosphorescent materials, which continue to emit light for some time after.
What can be diagnosed using fluorescence microscopy?
In the life sciences fluorescence microscopy is a powerful tool which allows the specific and sensitive staining of a specimen in order to detect the distribution of proteins or other molecules of interest. As a result, there is a diverse range of techniques for fluorescent staining of biological samples.
How is fluorescence detected?
UV detectors rely on the characteristics of many molecules to absorb energy when exposed to certain wavelengths of light. When these electrons return to the ground state and light is emitted, the process is referred to as fluorescence. Fluorescence detectors rely on this molecular property for detection.
Which detector is used in fluorimetry?
Fluorescence detectors are often used in series with a variable wavelength UV detector, so both signals can be monitored for optimal sensitivity and selectivity.
Is fluorescence proportional to concentration?
Fluorescence spectroscopy can be used to measure the concentration of a compound because the fluorescence intensity is linearly proportional to the concentration of the fluorescent molecule.
What is the principle of fluorescence spectroscopy?
Fluorescence describes a phenomenon where a molecular system absorbs, then emits light. In absorption high energy (short wavelength) light excites the system, promoting electrons within the molecule to transition from the ground state, to the excited state (see below).
What is fluorescence intensity measured in?
The intensity of the fluorescent signal is usually relative to other measurements or to a refence measurement taken by an instrument. Consequently, fluorescence plate readers measure the light signal emitted by a sample in Relative Fluorescent Units (RFU).
What is true quenching?
Quenching refers to any process which decreases the fluorescence intensity of a given substance. A variety of processes can result in quenching, such as excited state reactions, energy transfer, complex-formation and collisional quenching. Quenching is the basis for Förster resonance energy transfer (FRET) assays.
What are the factors that affect intensity name 4?
Some factors that affect intensity are the distance away from the epicenter, the depth of the earthquake, the population density of the area affected by the earthquake, the local geology of the are, the type of building construction in the area, and the duration of the shaking.
What factors influence where earthquakes occur?
Ground shaking is the primary cause of earthquake damage to man-made structures. Many factors influence the strength of earthquake shaking at a site including the earthquake’s magnitude, the site’s proximity to the fault, the local geology, and the soil type.