Albumin, serum reaction with azide

The reaction mixture for /3-galactosidase contained in a final volume of 0.5 mL 50 mM sodium citrate buffer (pH 3.5), 0.1 U/mL of /3-galactosidase, 1 mg/mL of bovine serum albumin, 0.02% sodium azide, 1 mM a-L-fucose (internal standard), and lactose (5-40 mM). The assay was conducted at 30°C. Aliquots of 20 fiL were removed at 8-minute intervals up to 48 minutes and added to 1 mL of distilled water at 4°C. The hydrolysis of substrate did not exceed 5%. Samples were desalted by passage through a column containing 0.2 mL each of Dowex AG50W-X12 (H+ form) and Dowex AG3-X4 (OH-form). The column was washed with 2 mL of distilled water and the eluate evaporated to dryness and taken up in water to give a lactose concentration of 0.2 mM. A 175 fiL aliquot was used for HPLC analysis. 

By means of the azide reaction N-carbobenzoxy 3,5 diiodothyronine was joined to horse serum globulin, albumin, and thyro-globulin (223). After iodination to form the thyroxyl compound anti sera to these, conjugated proteins were produced and the authors report that "passive immunization with anti sera to these derivatives protects against normal physiological effects of exogenously administered thyroglobulin and thyroxine. ... 

The RAFT polymerization of a -azido- u-dithiopyridine affords azide-terminated het-erotelechelic polymers which were reacted with biotin/avidine glutathion and bovin serum albumine via click and thiol-disulflde exchange reactions... 

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