Preparation of a novel targeted MR contrast agent Gd-DTPA-streptavidin and exploration of its reaction conditions

Abstract

Abstract: Objective To explore the optimal reaction condition of D TP A-coupled streptavidin labeled with gadolinium ion.Methods The number streptav idin-coupled of gadolinium ions and maximum biotin-binding capacity of Gd-DTPA-S A complex were analyzed at different DTPA-to-SA molar ratios (1000, 500, 200, 100) and in buffer solutions of different pH values (pH 5, 6, 7, and 8, respectiv ely).Results The number of streptavidin-coupled gadolinium ions increased with the pH value of the reaction system. When the DTPA-to-SA molar ratio was below 500, the number of gadolinium ions that SA-DTPA coupled increased with the DTPA -to-SA molar ratio, but tended to decrease when the ratio was 1000. No signific ant difference in the maximum biotin-binding capacity of Gd-DTPA-SA complex was noted between the groups.Conclusion The number of gadolinium ions that s treptavidin coupled depends on the pH value of the reaction system and DTPA-to-S A molar ratio, but the maximum biotin-binding capacity of Gd-DTPA-SA complex is not affected by the reaction conditions.

CLC Number:

LIU Xian, XU Yi-kai, HUANG Qi-liu. Preparation of a novel targeted MR contrast agent Gd-DTPA-streptavidin and exploration of its reaction conditions[J]. Journal of Southern Medical University, 2004, 24(01): 15-17.

References

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