Streptavidin conjugates are widely used together with a conjugate of biotin for specific detection of a variety of proteins, protein motifs, nucleic acids and other molecules since streptavidin has a very high binding affinity for biotin. This Texas Red-streptavidin conjugate comprises streptavidin (as the biotin-binding protein) with Texas Red covalently attached (as the fluorescent label). Our Texas Red-streptavidin conjugate was prepared using AAT Bioquest’s proprietary labeling technology. It demonstrated much brighter signal compared to the similar Texas Red-streptavidin conjugates from other commercial sources, thus can significantly increase assay sensitivities. It is commonly used as a second step reagent for indirect immunofluorescent staining, when used in conjunction with biotinylated primary antibodies. It is a valuable tool for biotin-streptavidin-based biological assays and tests using flow cytometry with a Texas Red filter set. A variety of the complementary biotinylated reagents are available from numerous commercial vendors.