Chemical modification refers to a number of various processes involving the alteration of the chemical constitution or structure of molecules.

In chemistry

Chemical modification describes the conversion of macromolecules through a chemical reaction or series of reactions.

Chemically modified electrodes

Chemically modified electrode A chemically modified electrode is an electrical conductor that has its surface modified for different electrochemical functions. Chemically modified electrodes are made using advanced approaches to electrode systems by adding a thin film or layer ...

s are electrodes that have their surfaces chemically converted to change the electrode's properties, such as its

physical Physical may refer to: *Physical examination In a physical examination, medical examination, or clinical examination, a medical practitioner examines a patient for any possible medical signs or symptoms of a medical condition. It generally co ...

chemical A chemical substance is a form of matter having constant chemical composition and characteristic properties. Some references add that chemical substance cannot be separated into its constituent elements by physical separation methods, i.e., wi ...

electrochemical Electrochemistry is the branch of physical chemistry concerned with the relationship between electrical potential difference, as a measurable and quantitative phenomenon, and identifiable chemical change, with the potential difference as an outco ...

optical Optics is the branch of physics that studies the behaviour and properties of light, including its interactions with matter and the construction of instruments that use or detect it. Optics usually describes the behaviour of visible, ultraviole ...

electrical Electricity is the set of physical phenomena associated with the presence and motion of matter that has a property of electric charge. Electricity is related to magnetism, both being part of the phenomenon of electromagnetism, as described by ...

, and

transport Transport (in British English), or transportation (in American English), is the intentional movement of humans, animals, and goods from one location to another. Modes of transport include air, land (rail and road), water, cable, pipeline, an ...

characteristics. These electrodes are used for advanced purposes in research and investigation.Durst, R., Baumner, A., Murray, R., Buck, R., & Andrieux, C.,
Chemically modified electrodes: Recommended terminology and definitions (PDF)
, IUPAC, 1997, pp 1317–1323.

In biochemistry

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 ...

, chemical modification is the technique of anatomically reacting a

protein Proteins are large biomolecules and macromolecules that comprise one or more long chains of amino acid residues. Proteins perform a vast array of functions within organisms, including catalysing metabolic reactions, DNA replication, respo ...

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 ...

with a reagent or reagents. Obtaining laboratory information through chemical modification which can be utilized to: * identify which parts of a molecule are exposed to a solvent. * determine which residues are important for a particular phenotype, e.g., which residues are important for an enzymatic activity; * introduce new groups into a macromolecule; and * crosslink macromolecules intra- and intermolecularly.

Chemical modification of protein side chains

Iodoacetamide 2-Iodoacetamide is an alkylating agent used for peptide mapping purposes. Its actions are similar to those of iodoacetate. It is commonly used to bind covalently with the thiol group of cysteine so the protein cannot form disulfide bonds. Also use ...

Iodoacetic acid Iodoacetic acid is a derivative of acetic acid. It is a toxic compound, because, like many alkyl halides, it is an alkylating agent. It reacts with cysteine residues in proteins. It is often used to modify SH-groups to prevent the re-formation ...

PEGylation PEGylation (or pegylation) is the process of both covalent and non-covalent attachment or amalgamation of polyethylene glycol (PEG, in pharmacy called macrogol) polymer chains to molecules and macrostructures, such as a drug, therapeutic protein ...

* BisSulfosuccinimidyl suberate *

1-Ethyl-3-(3-dimethylaminopropyl)carbodiimide 1-Ethyl-3-(3-dimethylaminopropyl)carbodiimide (EDC, EDAC or EDCI) is a water-soluble carbodiimide usually handled as the hydrochloride. It is typically employed in the 4.0-6.0 pH range. It is generally used as a carboxyl activating agent for the ...

* N-Ethylmaleimide * Methyl methanethiosulfonate *

MTSL MTSL (''S''-(1-oxyl-2,2,5,5-tetramethyl-2,5-dihydro-1H-pyrrol-3-yl)methyl methanesulfonothioate) is an organosulfur compound that is used as a nitroxide spin label.Christian Altenbach, Kyoung-Joon Oh, René J. Trabanino, Kálmán Hideg, Wayne L. ...

References

Protein structure {{Protein-stub