Disulfide 2-mercaptoethylamine

The use of a 500-fold molar excess of 2-mercaptoethylamine over the concentration of antibody presence was found to result in a partially reduced antibody in which two disulfides were reduced to yield four thiols (Sun et al., 2005). This strategy can be used to retain a biospecific antibody construct for subsequent discrete conjugation at the hinge region between the heavy chains. 

Figure 1.77 Disulfide reducing agents such as 2-mercaptoethylamine can be used to cleave the disulfide bonds in the hinge region of antibody molecules. Either intact IgG molecules or F(ab )2 fragments may be reduced in this manner to yield monofunctional antigen binding fragments.

For reduction of the cystamine disulfides, add 20 pi of 1.0 M DTT and incubate at room temperature for 15 minutes. This will release 2-mercaptoethylamine from the cystamine modification site and create the free sulfhydryl on the 5 terminus of the oligonucleotide. 

The unique characteristics of DTT and DTE are mainly reflected in their ability to form intramolecular ring structures upon oxidation. Disulfide reductants such as 2-mercaptoethanol, 2-mercaptoethylamine, glutathione, thioglycolate, and 2,3-dimercaptopropanol cleave disulfide bonds in a two-step reaction that involves the II formation of a mixed disulfide (Fig. 66). In the second stage of the reducing process, the... 

Reduction of the cystamine-labeled oligo using a disulfide reducing agent releases 2-mercaptoethylamine and creates a thiol group (Fig. 399). DNA probes labeled in this manner have been successfully conjugated with SPDP-activated alkaline phosphatase (Chapter 16, Section 1.5, and Section 2.4), maleimide-activated horseradish peroxidase (section 3.8.1), NHS-LC-biotin (Chapter 8, Section 3.1, and Section 2.3), and the fluorescent tag AMCA-HPDP (Chapter 8, Section 1.3, and Section 2.5). 

The reaction of cyclohexanone with bis(2-aminoethyl)disulfide, under nitrogen and in the presence of toluene-p-sulfonic acid, afforded the dihy-drothiazine 117 and 2-mercaptoethylamine, probably by way of the intermediate 116 cyclooctanone, 2,6-dimethylheptan-4-one, and isopropyl phenyl ketone behaved similarly. ... 

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