Bio-Rad StarBright Blue 520 Fluorescent Secondary Antibodies

Bio-Rad Laboratories has announced the StarBright Blue 520 Fluorescent Secondary Antibodies — fluorescent dye-labelled secondary antibodies for use in multiplex western blotting. They are said to exhibit a two- to threefold lower limit of detection than traditional green emission fluorophore-labelled antibodies such as Alexa Fluor 488 or DyLight 488, the current industry standards.

Bio-Rad created the StarBright Blue line of secondary antibodies to enable sensitive fluorescent detection, short exposure times and easy multiplexing for western blotting. The plug-and-play antibodies allow simultaneous detection of up to three proteins (two targets of interest and one housekeeping protein) on the same blot when used with the hFAB Rhodamine Housekeeping Protein Fluorescent Primary Antibodies. The antibodies work seamlessly on nitrocellulose or low-fluorescence PVDF membranes and all other aspects of the standard western blotting workflow remain unchanged.

The antibodies are labelled with a bright fluorescent dye, resulting in short exposure times and a high signal-to-noise ratio. This property stems from the presence of multiple donor-acceptor pairs in each polymer molecule, which enable it to efficiently absorb and emit light. The product’s 520 nm emission wavelength means the StarBright Blue 520 Fluorescent Secondary Antibody can pair with a StarBright Blue 700 Fluorescent Secondary Antibody or with other traditional fluorescent antibodies. It conjugates to highly cross-adsorbed IgG, which leads to low non-specific binding.

The antibodies can detect low-abundance protein targets in exposure times that are two to four times shorter than those of traditional fluorescent antibodies, according to the company.