Quanta BioDesign's DSPE dPEG® derivatives create liposomes and micelles of superior quality. We combine the phospholipid 1,2-Distearoyl-sn-glycero-3-phosphorylethanolamine (DSPE) with our single molecular weight discrete PEG linkers and spacers to create a product with a single chain length and molecular weight. Competing products composed of non-uniform (aka, polydispersed) PEG linkers and spacers create many products with different molecular weights and chain lengths. Analyzing Quanta BioDesign's DSPE dPEG® derivatives is simple because each one is a single, uniform product. Analyzing our competitor's products is not quite as easy.
Labeled DSPE dPEG® Derivatives
Insert a labeled DSPE-dPEG® compound into liposomes and micelles.
- The available labels are DOTA-tris(acid), 5(6)-carboxyfluorescein, and biotin.
- When chelated to metals, DOTA-tris(acid) is used in PET and SPECT imaging and radioisotope-based therapies and as an MRI contrast agent. Our DSPE dPEG® derivatives include PN11384, DOTA-tris(acid)-dPEG®24-amido-dPEG®24-DSPE, a DSPE-functionalized, DOTA-tris(acid)-terminated discrete PEG product equivalent to dPEG®48. The linker molecular weight is 2256 Daltons.
- 5(6)-carboxyfluorescein is a mixed-isomer fluorescent dye that is spectrally equivalent to fluorescein and FITC. It is used to track liposomes' and micelles' intracellular and intercellular movements. PN11385, 5(6)-carboxyfluorescein-dPEG®24-amido-dPEG®24-DSPE combines 5(6)-carboxyfluorescein with a 2256 Dalton dPEG® linker and the phospholipid DSPE.
- Biotin binds with avidin and streptavidin and can be used to capture liposomes or micelles in, for example, a pretargeted drug delivery application. PN11386, Biotin-dPEG®4-amido-dPEG®24-amido-dPEG®24-DSPE, combines a DSPE-terminated 2504 Dalton dPEG®52 spacer with biotin.
Try any or all of these products today and discover the dPEG® difference!
Methoxy-terminated DSPE dPEG® Derivatives
To provide a neutral surface change on liposomes and micelles, try our methoxy-terminated DSPE dPEG® derivatives. We offer various discrete PEG chain lengths functionalized with the phospholipid DSPE for insertion into the liposomes and micelles and terminated with a methoxy group. These DSPE dPEG® derivatives increase hydrophilicity and protect liposomes and micelles from opsonization by serum proteins of the MPS by creating a steric barrier, as shown in the graphical representation on the left.
Click here to see all products in this group.
Individual products by name (in order of increasing chain length and molecular weight):
| Product Number | Product Name | dPEG® Molecular Weight (Da) |
| 11024 | m-dPEG®8-DSPE | 395 |
| 11373 | m-dPEG®25-DSPE | 1144 |
| 11094 | m-dPEG®12-amido-dPEG®24-DSPE | 1700 |
| 11095 | m-dPEG®25-amido-dPEG®24-DSPE | 2272 |
NOTE: The dPEG® molecular weight correlates with the PEG chain length. PEG molecular weights up to 2 kDa protect liposomes and micelles from opsonization, but there is little benefit to PEG molecular weights beyond 2 kDa. Indeed, too big a PEG chain can inhibit the cellular uptake of liposomes and micelles. Moreover, a 2 kDa dPEG® linker or spacer is not always needed. The amount of PEG needed depends on the application and may require empirical determination of the optimum size.
DSPE dPEG® Derivatives with Reactive Terminal Groups
DSPE dPEG® derivatives with reactive terminal groups are useful for functionalizing the surfaces of liposomes and micelles. These reactive groups can conjugate antibodies, antibody fragments, peptides, small-molecule drugs, and many other molecules through reactions with amines (TFP ester), sulfhydryl groups (maleimide), and azide (DBCO). Applications include, but are not limited to, cellular targeting and drug delivery.
Product Number 11029, TFP-dPEG®13-DSPE
- PN11029, TFP-dPEG®13-DSPE has an amine-reactive 2,4,5,6-tetrafluorophenyl ester group.
- The discrete PEG (dPEG®) spacer is 43 atoms and 50.0 Å long.
- Potential applications include conjugation to a targeting biomolecule such as an antibody, antibody fragment, or peptide, or a small molecule drug.
- Click here or here to learn more about using TFP esters as alternatives to NHS esters.
DSPE dPEG® Derivatives with Terminal Maleimide Moieties
- Product number 11028 has a MAL-dPEG®12 conjugated to the DSPE group.
- Product numbers 11093 and 11388 have dPEG®48 and dPEG®72 spacers, respectively.
- The maleimide reactive group conjugates to free thiols selectively below pH 7.5.
- Conjugate peptides, antibodies, or antibody fragments to the maleimide groups for surface functionalization of a liposome or micelle.
- Please see our Maleimide Reaction Chemistry page for more information about maleimide reactivity.
Click Chemistry Bioconjugation for Liposomes and Micelles
- Product number 11383 is the first in our line of copper-free click chemistry DSPE dPEG® derivatives.
- Use strain-promoted azide-alkyne cycloaddition (SPAAC) to conjugate azides and alkynes without potentially cytotoxic copper.
- Learn more about Click Chemistry with dPEG® Products by clicking the link.