Ligand Displacement Fluorescence Immunoassay for Gentamicin and Human IgG#

The authors acknowledge the excellent technical work of R. C. Wong.

Abstract

A ligand displacement fluorescence immunoassays (LD‐FIA) for serum gentamicin and for human IgG have been developed. The LD‐FIA for gentamicin used affinity purified anti‐gentamicin antibodies immobilized onto ¼ inch polystyrene balls by adsorption. The immobilized anti‐gentamicin antibodies were presaturated with fluorescein labeled gentamicin to form an immuno‐complex consisting of fluorescein labeled gentamicin bound to anti‐gentamicin antibodies coated balls (F‐GAB). F‐GAB released the fluorescein labeled gentamicin upon contact with the gentamicin containing sample. The amount of released fluorescein labeled gentamicin is directly proportional to the amount of gentamicin in the test serum. LD‐FIA for human IgG was constructed in a similar way using immobilized antihuman IgG and fluorescein labeled human IgG.

LD‐FIA is a rapid and convenient immuno‐analytical technique that requires minimal manipulation, (i.e., it only requires the addition of diluted sample to one reagent—the F‐GAB). The technique can be used for determining either small molecules or macromolecules as demonstrated here.

The authors acknowledge the excellent technical work of R. C. Wong.

Keywords:

• Displacement immunoassay
• gentamicin
• IgG
• fluorescein

Notes

The authors acknowledge the excellent technical work of R. C. Wong.