Functional Group | Biotin |
Storage | Should always be stored at in the dark at 4 °C, except when brought to room temperature for brief periods prior to animal dosing. DO NOT FREEZE. If the suspension is frozen, the encapsulated drug can be released from the liposomes thus limiting its effectiveness. In addition, the size of the liposomes will also change upon freezing and thawing. |
Appearance | White translucent liquid made of nano size unilamellar liposomes. Usually due to the small size of liposomes no settling will occur in the bottom of the vial. The liposomes are packaged in an amber vial. |
Description | Biotinylated liposomes can be conjugated noncovalently with (strept)avidin through either direct interaction with the protein/antibody conjugated to (strept)avidin or by coupling with other biotinylated proteins using (strept)avidin as a bridging molecule. Both avidin and streptavidin form strong noncovalent bond with biotin. The high resistance to breakdown makes them very useful in bioconjugate chemistry. However, streptavidin has replaced avidin in most bioconjugation applications due to its enhance properties. NeutrAvidin (ThermoFisher) is a modified avidin without negative properties. It performs much better than original avidin and sometimes streptavidin. In order to exploit the high-affinity interaction of biotin with strept(avidin), a two-step “sandwich” protocol (Method A) has been developed for the preparation of targeted immunoliposomes. In this methodology, (strept)avidin is first attached to biotinylated liposomes, then a biotin-modified protein/antibody is introduced into the biotinylated strept(avidin)-labeled liposomes. This noncovalent approach is rapid, extremely versatile and applicable to numerous targeting ligands of interest with respect to in vitro and in vivo applications. Alternatively, instead of forming a strept(avidin) bridge, strept(avidin) molecule can also be covalently conjugated to antibody or ligand (Method B) and non-covalently bound to liposomes containing biotin on surface in order to form immunoliposomes. |
Lipid composition | L-a-PC/Cholesterol/1,2-Distearoyl-sn-glycero-3-phosphoethanolamine-N-(biotinyl) (69/30/1 molar ratio) |
Liposome Size | 100 nm |
Lipid Molar Concentration | 22.45 mM |
Buffer | Phosphate Buffered Saline, pH 7.4 |
Shelf-life | 4 months. |
Technical Notes | To avoid precipitation of lipid in the noncovalent approach, care needs to be employed in maintaining a high ratio of strept(avidin) to biotin-liposomes. Otherwise, the coupling efficiencies would be relatively low. Alternatively, Sepharose? CL-4B size exclusion spin column can be used instead of Float-A-Lyzer?. However keep in mind that a large amount of liposomes will be loss on the column during the process. Dialysis is a much slower process that size exclusion however there will be minimal loss of liposomes. If you decide to use a dialysis cassette, you will need to make sure that the MWCO is below 1,000,000 dalton. At 1,000,000 dalton, the pore size on the dialysis membrane gets close to 100 nm and therefore, your liposomes can be dialyzed out. You cannot use dialysis cassettes and spin columns blindly. They come in various sizes and you need to choose the correct size wisely. If you are using a ligand or peptide that is hydrophobic then it is recommended to solubilize it in DMSO or DMF and then add the buffer to it. It is recommended not to use more than 5% volume of DMSO or DMF in the solution. DMF and DMSO are both compatible with liposomes and they are also miscible in water. Other organic solvent such as ethanol and chloroform are not compatible with liposomes and will cause the liposomes to lyse. If you end up using DMSO or DMF then after the conjugation reaction is done, you need to remove DMSO and DMF from the liposomes. In order to do that you need to use a dialysis cassette that is made from REGENERATED CELLULOSE MEMBRANE. NOTE: Not all membranes are compatible with DMF and DMSO. We recommend using a Slide-A-Lyzer? MINI Dialysis Device with MWCO of 2K made from regenerated cellulose membrane manufactured by ThermoFisher. After DMSO or DMF is removed, you can use Float-A-Lyzer? dialysis device for the final step of cleaning up the prep. |
Lipid Mass Concentration | 14.82 mg/mL |
Product Name | Catalog | Lipid composition | Liposome Size | Price |
---|---|---|---|---|
Clipos™ Biotin Liposomes, Non PEGylated | CDEIMS-1528 | L-a-PC/Cholesterol/1,2-Dioleoyl-sn-glycero-3-phosphoethanolamine-N-(cap biotinyl) (69/30/1 molar ratio) | 100 nm | $1480 |
Clipos™ Biotin Liposomes, Non PEGylated | CDEIMS-1525 | HSPC/Cholesterol/DSPE-PEG(2000)/DSPE-PEG(2000)-Biotin (57/38/4/1 molar ratio) | 100 nm | $1480 |
1. Download the template.
2. Enter product information on the template (maximum number of products: 200).
3. Load the file using selector below.
1. Download the template.
2. Enter product information on the template (maximum number of products: 200).
3. Load the file using selector below.