Influence of the antibody-peroxidase coupling methods on the conjugate stability and on the methodologies for the preservation of the activity in time.
We studied the influence of conjugation methods and storage conditions on the stability of immunoconjugates with peroxidase. We demonstrate here that conjugates formed by the maleimide-sulfhydryl method and by the periodate oxidation method lose activity when maintained in diluted solutions. However, while the loss of activity of MSM conjugates is due exclusively to hydrolysis of the thioether bond, the loss of activity of periodate complexes is caused by a reduction of both the enzymatic and antibody immunochemical activities. Based on these observations, we developed a buffer that stabilizes the thioether bond, thus permitting long time storage of these immunoconjugates at low concentration and at above freezing temperatures.
Presentini
R
R
Sclavo Diagnostics Srl, R/D Department, Siena, Italy.
Terrana
B
B
D000906:Antibodies / Q000737:chemistry*; D002021:Buffers; D004789:Enzyme Activation; D004795:Enzyme Stability; D006735:Horseradish Peroxidase; D006801:Humans; D018796:Immunoconjugates / Q000737:chemistry*; D007124:Immunoenzyme Techniques; D007074:Immunoglobulin G / Q000737:chemistry; D008301:Maleimides; D010504:Periodic Acid; D013439:Sulfhydryl Reagents
D000906:Antibodies; D002021:Buffers; D018796:Immunoconjugates; D007074:Immunoglobulin G; D008301:Maleimides; D013439:Sulfhydryl Reagents; D010504:Periodic Acid; C009288:metaperiodate; D006735:Horseradish Peroxidase