Detection of hIgG with SRB-encapsulated Liposome Biosensor

Abstract

Abstract: Abstract：Purpose: In this study, we make a study on the detection of hIgG with SRB-encapsulated liposome fluoroimmunoassay. Methods: An immunoliposome encapsulating sulforhodamine B sodium salt (SRB) was prepared as fluorescent biosensor with film disperse method. Magnetic beads modified goat anti-human IgG antibody (MB modified anti-IgG) were employed as immobilizing and separating carrier. By enzyme-linked immunospecific assay (ELISA) method, MB modified anti-IgG were linked to SRB-encapsulated liposomes, which were twinkly released a great quantity of SRB molecules upon alcohol addition, resulting in detecting human IgG (hIgG) with high fluorescent sensitivity. This method clarified that SRB liposomes had good stability in 10 days. The optimization condition was as follows: the amount of MB modified anti-body was 60μg and biotin-labled anti-IgG was 0.2μg. Results: The lowest detectable concentration of hIgG was 1 ng/mL(～6.25pM), and the range of standard curve were 1～200 ng /mL. Conclusions: This lable-free protocol would be a potential fluorescent enlarging tool for the determination of in other bio-analytes grounded on the simple, fast and high sensitive analysis.

Key words: Key words：liposomes, magnetic beads, immunoglobulin, biosensor, fluorescent analysis

CLC Number:

Q511

References

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