Cross-bridge cleavable

Figure 4.6 DSS reacts with two amine-containing molecules to form amide bond crosslinks. The cross-bridge is non-cleavable.

Figure 4.7 DST may be used to crosslink amine-containing molecules, forming amide bond linkages. The central diol of the cross-bridge is cleavable by treatment with sodium periodate.

Figure 4.9 EGS reacts with amine-containing molecules to form amide linked conjugates. The ester groups within its cross-bridge are cleavable under alkaline conditions using hydroxylamine.

Figure 4.21 BASED can react with molecules after photoactivation to form crosslinks with nucleophilic groups, primarily amines. Exposure of its phenyl azide groups to UV light causes nitrene formation and ring expansion to the dehydroazepine intermediate. This group is highly reactive with amines. The cross-bridge of BASED is cleavable using a disulfide reducing agent.

Figure 5.1 The general design of a heterobifunctional crosslinking agent includes two different reactive groups at either end and an organic cross-bridge of various length and composition. The cross-bridge may be constructed of chemically cleavable components for selective disruption of conjugates.

Figure 28.10 Trifunctional label transfer agents contain two arms with terminal reactive groups and a third arm with a label or affinity tag, such as a biotin group. One of the reactive groups typically is thermoreactive to couple with bait proteins, while the second reactive group usually is photoreactive. The thermoreactive arm has a cleavable cross-bridge to facilitate release of the captured protein and transfer of the label of affinity tag to it.

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