SDIP/Europium for membrane fusion assay

Biotium developed SDIP/Eu³ as an alternative to DPA/Tb³ , which is used for vesicle fusion assays. Similar to DPA/TB ³ assay, one population of vesicles can be loaded with the chelator SDIP while another population of vesicles can be loaded with EuCl₃. Intense red fluorescence is produced when the two types of vesicles fuse as a result of formation of the SDIP/Eu³ complex. The main advantage of SDIP/Eu³ over DPA/TB³ is that the SDIP/Eu³ generates fluorescent emission with brighter intensity and much longer wavelength. Each set of products contain 10 mg SDIP and 25 mg EuCl₃ in two separate vials.

• &lamba; Abs/&lamba; Em(for complex) = 250 ca.320/ca.610 nm
• SDIP is a light yellow solid
• EuCl³ is in a colorless crystal
• Both are readily soluble in water
• Both components are stable at room temperature or 4C
• Aqueous solutions of SDIP should be protected from light
• MW of SDIP: 449
• MW of EuCl³: ca.258