Cy5 dic18 | CAS 75539-51-4

Cy5 dic18 is a cyanine-based, lipophilic fluorescent dye designed for membrane-associated labeling in fluorescence workflows. With its long hydrophobic character, it partitions into lipid environments and provides strong fluorescence for tracking membrane localization, lipid mixing, and membrane dynamics using standard fluorescence imaging instrumentation.

1. Membrane Labeling Studies

Cy5 dic18 is frequently used to visualize and quantify cell or model-membrane association in fluorescence microscopy experiments. Researchers label lipid-containing structures such as plasma membranes, supported lipid bilayers, and liposome membranes to monitor distribution and redistribution during experimental perturbations. The dye's hydrophobic nature supports robust partitioning into lipid phases, enabling membrane-centric readouts in imaging-based workflows where dye localization is the primary experimental variable.

2. Liposome And Vesicle Tracking

Cy5 dic18 is also applied in vesicle and nanoparticle fluorescence studies, where membrane labeling is required to follow vesicle integrity, trafficking, or fusion events. In typical experimental designs, the dye is incorporated into liposomal membranes prior to use, allowing subsequent fluorescence imaging or plate-based fluorescence measurements of vesicle behavior in mixed systems. This makes Cy5 dic18 useful for membrane interaction assays in materials science and chemical biology, particularly when membrane labeling rather than soluble labeling is the desired outcome.

3. FRET Pair Construction

Cy5 dic18 is commonly selected as a Cy5-channel component in FRET-based assay development, where an emission acceptor in the far-red region supports donor-acceptor fluorescence readouts. In these workflows, researchers pair Cy5 dic18 with an appropriate donor fluorophore to create distance- or proximity-dependent signal changes for membrane proximity studies, polymer or biomaterial assembly monitoring, and labeled conjugate characterization. The dye's far-red emission positioning helps reduce spectral overlap in multicolor fluorescence setups when the donor and acceptor are chosen to match the instrument filter set.

4. Fluorescence-Based Bioassay Readouts

Cy5 dic18 is used as a fluorescent reporting label in assay formats that rely on membrane-associated fluorescence changes, including endpoint fluorescence measurements and kinetic monitoring in microplate readers. Chemical biology and biomaterials teams often incorporate the dye into membrane-containing assay systems to track binding-driven membrane association, membrane disruption, or lipid mixing readouts. This application is particularly relevant when the experimental design benefits from a dye that reports on lipid-phase localization rather than on a soluble target.