HBC 530

HBC 530 may be used in the imaging of matrix metalloproteinase 2 (MMP-2) by protein-nucleic chimeric probe (PNCP) in the extracellular matrix (ECM).

HBC 530 selectively binds to the Pepper RNA aptamer with high affinity (Kd ~ 3.5 nM; kon = 6.6 × 105 M−1 s−1 and koff = 0.0023 s−1) in a 1:1 stoichiometry, where binding is critically dependent on Mg2+ ions (optimal at 5 mM) and results in significant fluorescence enhancement (3,595-fold; λex/λem ~485/530 nm; ϵ ~ 65,000 M-1cm-1; ɸAptamer:Ligand ~ 0.66). HBC-530 intercalates in the RNA binding pocket between a base quadruple and G·U wobble pair, forming a stable complex via H-bond to G41-N7 for robust, background-free imaging. At 1 μM concentration with 20 mM MgSO4, HBC530 permeates cells for real-time RNA imaging, enabling tracking of RNA localization, dynamics, and gene expression.