Guanidinium thiocyanate (GTC) or guanidinium isothiocyanate (GITC) is a

chemical compound A chemical compound is a chemical substance composed of many identical molecules (or molecular entities) containing atoms from more than one chemical element held together by chemical bonds. A molecule consisting of atoms of only one element ...

used as a general protein denaturant, being a

chaotropic agent A chaotropic agent is a molecule in water solution that can disrupt the hydrogen bonding network between water molecules (i.e. exerts chaotropic activity). This has an effect on the stability of the native state of other molecules in the solution, ...

, although it is most commonly 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 ...

protector in the extraction of DNA and

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 ...

from cells. GITC may also be recognized as guanidine thiocyanate. This is because guanidinium is the conjugate acid of

guanidine Guanidine is the compound with the formula HNC(NH2)2. It is a colourless solid that dissolves in polar solvents. It is a strong base that is used in the production of plastics and explosives. It is found in urine predominantly in patients experie ...

and is called the

guanidinium cation Guanidine is the compound with the formula HNC(NH2)2. It is a colourless solid that dissolves in polar solvents. It is a strong base that is used in the production of plastics and explosives. It is found in urine predominantly in patients expe ...

, H₆N₃sup>+.

Uses

Guanidinium thiocyanate can be used to deactivate a

virus A virus is a submicroscopic infectious agent that replicates only inside the living cells of an organism. Viruses infect all life forms, from animals and plants to microorganisms, including bacteria and archaea. Since Dmitri Ivanovsky's 1 ...

, such as the

influenza virus ''Orthomyxoviridae'' (from Greek ὀρθός, ''orthós'' 'straight' + μύξα, ''mýxa'' 'mucus') is a family of negative-sense RNA viruses. It includes seven genera: ''Alphainfluenzavirus'', ''Betainfluenzavirus'', '' Gammainfluenzavirus'', ...

that caused the 1918 "

Spanish flu The 1918–1920 influenza pandemic, commonly known by the misnomer Spanish flu or as the Great Influenza epidemic, was an exceptionally deadly global influenza pandemic caused by the H1N1 influenza A virus. The earliest documented case was ...

", so that it can be studied safely. Guanidinium thiocyanate is also used to lyse cells and virus particles in RNA and DNA extractions, where its function, in addition to its lysing action, is to prevent activity of RNase enzymes and DNase enzymes by denaturing them. These enzymes would otherwise damage the extract. A commonly used method is

guanidinium thiocyanate-phenol-chloroform extraction Acid guanidinium thiocyanate-phenol-chloroform extraction (abbreviated AGPC) is a liquid–liquid extraction technique in biochemistry. It is widely used in molecular biology for isolating RNA (as well as DNA and protein in some cases). This metho ...

. It is not strictly necessary to use phenol or chloroform if extracting RNA for

Northern blot The northern blot, or RNA blot,Gilbert, S. F. (2000) Developmental Biology, 6th Ed. Sunderland MA, Sinauer Associates. is a technique used in molecular biology research to study gene expression by detection of RNA (or isolated mRNA) in a sample.K ...

ting or DNA for Southern blot analysis because the gel electrophoresis followed by transfer to a membrane will separate the RNA/DNA from the proteins. Additionally, since these methods use probes to bind to their conjugates, peptides that get through the process don't generally matter unless a peptide is an RNase or DNase, and then only if the enzyme manages to renature, which should not occur if proper protocols are followed. A possible exception might be when working with temperature extremophiles because some enzymes of these organisms can remain stable under extraordinary circumstances.

Preparation

This substance can be prepared by reacting guanidinium carbonate with

ammonium sulfate Ammonium sulfate (American English and international scientific usage; ammonium sulphate in British English); (NH4)2SO4, is an inorganic salt with a number of commercial uses. The most common use is as a soil fertilizer. It contains 21% nitrogen a ...

ammonium thiocyanate Ammonium thiocyanate is an inorganic compound with the formula NH4SCN. It is the salt of the ammonium cation and the thiocyanate anion. Uses Ammonium thiocyanate is used in the manufacture of herbicides, thiourea, and transparent artificial resin ...

under heat. Another method is the pyrolysis of

thiourea Thiourea () is an organosulfur compound with the formula and the structure . It is structurally similar to urea (), except that the oxygen atom is replaced by a sulfur atom (as implied by the ''thio-'' prefix); however, the properties of urea ...

at 180°C.

References

{{DEFAULTSORT:Guanidinium Thiocyanate Thiocyanates Guanidinium compounds Chaotropic agents