Amino Acid Side Chain Modifiers

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A range of chemicals that modify amino acid side chains to block side chain interactions, change the charge or modify them to be more favorable for other reactions.

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4-Vinylpyridine is used as a derivatizing reagent for free thiols such as GSH. It is used in the Glutathione colorimetric assay to remove reduced GSH, so that the oxidized Glutathione (GSSG) concentra..

Citraconic Anhydride

Citraconic anhydride reacts with primary amines and blocks them by creating an amide linkage and a terminal carboxylate.   The linkage is stable at neutral to alkaline pH (pH >7) and at ..

L-Cysteine•HCl monohdyrate

L-Cysteine hydrochloride salt is routinely used with Ellman's Reagent assays as a sulfhydryl standard. In addition, it is also used as a supplement for protein refolding experiments.   ..

p-Hydroxyphenylglyoxal (HPG)

HPG (p-hydroxyphenylglyoxal) reacts to specifically modify arginine residues under mild conditions to yield spectrophotometrically measurable signal for amino acid detection.   Features of ..


  Features Chemical Name: N-Succinimidyl S-acetylthioacetate CAS Number: 76931-93-6 Molecular Weight: 245.25 Reacts primarily with primary amines Add..

Sodium meta-Periodate

Sodium metaperiodate, or sodium m-periodate, is a mild oxidant that is routinely used for the conversion of cis-glycol groups in carbohydrates to reactive aldehdye groups (Figure 1).  The reactiv..

Sulfo NHS

Features Chemical Name: N-Hydroxysulfosuccinimide Reacts primarily with primary amines Water soluble Molecular weight: 217.13   Applications Id..

Sulfo NHS Acetate

Features Chemical Name: Sulfosuccinimidyl acetate Reacts primarily with primary amines Reacts at pH 7-9 Water soluble Molecular weight: 259.17   ..


TNBS (2,4,6-trinitrobenzene sulfonic acid) is a highly sensitive and rapid chemical used to quantitate the free amino groups.  The reaction of TNBS with primary amines generates a highly chromoge..

Traut's Reagent

Features Chemical Name: 2-Iminothiolane hydrochloride Molecular weight: 137.63 Mild conditions: pH 7-10, 25°C Soluble in water   Applications ..