SYBR Green I (SG) is an asymmetrical
cyanine dye
Cyanines, also referred to as tetramethylindo(di)-carbocyanines are a synthetic dye family belonging to the polymethine group. Although the name derives etymologically from terms for shades of blue, the cyanine family covers the electromagnetic ...
used as a
nucleic acid
Nucleic acids are biopolymers, macromolecules, essential to all known forms of life. They are composed of nucleotides, which are the monomers made of three components: a 5-carbon sugar, a phosphate group and a nitrogenous base. The two main cl ...
stain
A stain is a discoloration that can be clearly distinguished from the surface, material, or medium it is found upon. They are caused by the chemical or physical interaction of two dissimilar materials. Accidental staining may make materials app ...
in
molecular biology
Molecular biology is the branch of biology that seeks to understand the molecular basis of biological activity in and between cells, including biomolecular synthesis, modification, mechanisms, and interactions. The study of chemical and physi ...
. The SYBR family of dyes is produced by
Molecular Probes Inc., now owned by
Thermo Fisher Scientific
Thermo Fisher Scientific Inc. is an American supplier of scientific instrumentation, reagents and consumables, and software services. Based in Waltham, Massachusetts, Thermo Fisher was formed through the merger of Thermo Electron and Fisher S ...
. SYBR Green I binds to
DNA. The resulting DNA-dye-complex best absorbs 497 nanometer blue light (λ
max = 497 nm) and emits green light (λ
max = 520 nm). The stain preferentially binds to double-stranded DNA, but will stain single-stranded (ss) DNA with lower performance. SYBR Green can also stain
RNA
Ribonucleic acid (RNA) is a polymeric molecule essential in various biological roles in coding, decoding, regulation and expression of genes. RNA and deoxyribonucleic acid ( DNA) are nucleic acids. Along with lipids, proteins, and carbohydra ...
with a lower performance than ssDNA.
Uses
SYBR Green finds usage in several areas of
biochemistry
Biochemistry or biological chemistry is the study of chemical processes within and relating to living organisms. A sub-discipline of both chemistry and biology, biochemistry may be divided into three fields: structural biology, enzymology and ...
and
molecular biology
Molecular biology is the branch of biology that seeks to understand the molecular basis of biological activity in and between cells, including biomolecular synthesis, modification, mechanisms, and interactions. The study of chemical and physi ...
. It is used as a dye for the quantification of double stranded DNA in some methods of
quantitative PCR
A real-time polymerase chain reaction (real-time PCR, or qPCR) is a laboratory technique of molecular biology based on the polymerase chain reaction (PCR). It monitors the amplification of a targeted DNA molecule during the PCR (i.e., in real ...
.
It is also used to visualise DNA in
gel electrophoresis
Gel electrophoresis is a method for separation and analysis of biomacromolecules ( DNA, RNA, proteins, etc.) and their fragments, based on their size and charge. It is used in clinical chemistry to separate proteins by charge or size (IEF ...
. Higher concentrations of SYBR Green can be used to stain
agarose gel
Agarose gel electrophoresis is a method of gel electrophoresis used in biochemistry, molecular biology, genetics, and clinical chemistry to separate a mixed population of macromolecules such as DNA or proteins in a matrix of agarose, one of the ...
s in order to visualise the DNA present. In addition to labelling pure nucleic acids, SYBR Green can also be used for labelling of DNA within cells for
flow cytometry
Flow cytometry (FC) is a technique used to detect and measure physical and chemical characteristics of a population of cells or particles.
In this process, a sample containing cells or particles is suspended in a fluid and injected into the flo ...
and
fluorescence microscopy
A fluorescence microscope is an optical microscope that uses fluorescence instead of, or in addition to, scattering, reflection, and attenuation or absorption, to study the properties of organic or inorganic substances. "Fluorescence microscop ...
. In these cases
RNase
Ribonuclease (commonly abbreviated RNase) is a type of nuclease that catalyzes the degradation of RNA into smaller components. Ribonucleases can be divided into endoribonucleases and exoribonucleases, and comprise several sub-classes within t ...
treatment may be required to reduce background from RNA in the cells.
Safety
SYBR Green I is marketed as a replacement for
ethidium bromide
Ethidium bromide (or homidium bromide, chloride salt homidium chloride) is an intercalating agent commonly used as a fluorescent tag (nucleic acid stain) in molecular biology laboratories for techniques such as agarose gel electrophoresis. It i ...
, a potential human
mutagen
In genetics, a mutagen is a physical or chemical agent that permanently changes nucleic acid, genetic material, usually DNA, in an organism and thus increases the frequency of mutations above the natural background level. As many mutations can ca ...
, as both safer to work with and free from the complex waste disposal issues of ethidium bromide. However any
small molecule
Within the fields of molecular biology and pharmacology, a small molecule or micromolecule is a low molecular weight (≤ 1000 daltons) organic compound that may regulate a biological process, with a size on the order of 1 nm. Many drugs ar ...
capable of binding DNA with high affinity is a possible
carcinogen
A carcinogen is any substance, radionuclide, or radiation that promotes carcinogenesis (the formation of cancer). This may be due to the ability to damage the genome or to the disruption of cellular metabolic processes. Several radioactive substan ...
, including SYBR Green.
In a study using the
Ames test, which measures the ability of chemicals to cause mutations, when assayed at the same concentration SYBR Green I was on the order of 30 times less mutagenic than ethidium bromide.
Similar cyanine dyes
*
PicoGreen (PG)
*
SYBR Safe
SYBR Safe is a cyanine dye used as a nucleic acid stain in molecular biology. SYBR Safe is one of a number of SYBR dyes made by the Life Technologies Corporation. SYBR Safe binds to DNA. The resulting DNA-dye-complex absorbs blue light (λmax = ...
*
SYBR Gold
SYBR Gold is an asymmetrical cyanine dye. It can be used as a stain for double-stranded DNA, single-stranded DNA, and RNA. SYBR Gold is the most sensitive fluorescent stain of the SYBR family of dyes for the detection of nucleic acids. The SYB ...
*
Thiazole orange
Thiazole, or 1,3-thiazole, is a heterocyclic compound that contains both sulfur and nitrogen. The term 'thiazole' also refers to a large family of derivatives. Thiazole itself is a pale yellow liquid with a pyridine-like odor and the molecular fo ...
(TO)
*
Oxazole yellow
Oxazole is the parent compound for a vast class of heterocyclic aromatic organic compounds. These are azoles with an oxygen and a nitrogen separated by one carbon. Oxazoles are aromatic compounds but less so than the thiazoles. Oxazole is a weak ...
(YO)
* Safe-Green
* Chai Green
See also
*
GelGreen
GelGreen is an intercalating nucleic acid stain used in molecular genetics for agarose gel DNA electrophoresis. GelGreen consists of two acridine orange subunits that are bridged by a linear oxygenated spacer.
Its fluorophore, and therefore its ...
__notoc__
Notes and references
{{DEFAULTSORT:Sybr Green I
Staining dyes
Cyanine dyes
Benzothiazoles
Quinolines
Dimethylamino compounds
Quaternary ammonium compounds