PromoFluor NIR Maleimides
Near infrared PromoFluor Maleimides for labeling thiol groups of proteins.
PromoFluor-670, PromoFluor-680, PromoFluor-700, PromoFluor-750, PromoFluor-770, PromoFluor-780 and PromoFluor-840 are next-generation long wavelength dyes representing a true breakthrough in the field. Other near-IR dyes suffer from problems of limited fluorescence brightness due to excessive dye aggregation and poor stability. The high water solubility of PromoFluor dyes means that a high dye-to-protein ratio can be attained without causing precipitation of the conjugates. PromoFluor NIR dyes are superior alternatives to the respective Alexa Fluor near-infrared dyes.
PromoFluor Maleimides are intended for covalently labeling biomolecules containing a thiol group (e.g. proteins). A neutral thiol-reactive label has little influence on the isoelectric point of a protein. In effect, PromoFluor Maleimides have an advantage over amino group labels because they do not interfere with techniques like differential 2D gel electrophoresis. Since most proteins contain only a few thiol functional groups, thiol-reactive dyes can be used to selectively modify a protein or peptide containing a thiol group at a specific site. Moreover, these dyes are well suited for labelling oligonucleotides. Maleimides couple to thiol groups under very mild conditions at a pH around 7.