Assay kit

Introduction

This assay kit uses NHS ester-activated fluorescein to label antibodies or proteins for immunostaining or cellular protein tracing. The activated fluorescein can directly form covalent bonds with target antibody proteins or other macromolecules containing primary amine groups. The kit includes dialysis tubes to remove unreacted fluorescein and other potentially interfering small molecules, such as Tris buffer and other amine compounds, which can interfere with the detection or labeling reaction. The labeling process is very simple: add NHS-Fluorescein (Reagent A) to the protein solution which remain above the dialysis membrane and incubate at 37°C for 10–30 minutes. Excess unreacted fluorescein molecules can be removed through the centrifugation. The excitation and emission wavelengths of the fluorescein-labeled protein are 500 nm and 525 nm, respectively. This kit contains all the necessary reagents for labeling, including a preservation solution for storing the labeled protein.