Fluorescent microscopic determination of proteins in human serum with the self-ordered ring of nuclear fast red formed on the solid support of glass slides

A self-ordered ring (SOR) technique based on the assembly of fluorescent molecules on the solid support of glass slides is presented for the detection of trace amount of proteins by using fluorescence microscope. At pH 6.62 and with the aid of poly(vinyl alcohol)-124 (PVA-124), a droplet of nuclear fast red (NFR) solution can form a fluorescent SOR on hydrophobic glass slide, and the presence of proteins can enhance its fluorescence intensity. When the volume of the droplet is 0.2 μl, linear response is observed in the range 0–100 pg, and the limit of determination is 2.44 pg for BSA and 0.91 pg for HSA (3σ). The results of determination for three human serum samples were identical with those obtained according to the Bradford method using Coomassie Brilliant Blue (CBB G-250).