How to calculate from molar ratio to weight of each components to make liposomes?

Dear Fransiska Christydira Sekaringtyas ,

There are several aspects that need to be taken into consideration. First is a well-understood concept on how to prepare liposomes, see for example: https://www.sigmaaldrich.com/NL/en/technical-documents/protocol/cell-culture-and-cell-culture-analysis/transfection-and-gene-editing/liposome-preparation

Second do realise that one important detail is missing in your question, 5 mL liposomes… at what (end-)concentration? Typical concentrations are 10mM or in terms of mg/mL typical values are 10-100 mg/mL, see for example Article Anionic phospholipids are essential for α-helix formation of...

So, let’s say you want a 10 mM stock solution. Using the molar ratio’s, you indicated this would mean:

DSPC 5.66 mM (mw 790.161 g·mol−1)

DOPE 2.87 mM (mw 744.034 g.mol-1)

PEG200-DSPE 1.47 mM (2790.521 g.mol-1, I suppose you meant PEG2000, https://avantilipids.com/product/880128)

Now it is pretty straight forward, 790.2 mg/mL would mean 1M DSPC, so 5.66/1000 x 790.2 mg/mL = 4.47 mg/mL would render 5.66 mM etc.

Hope this answers your question somewhat.

Best regards.

Fransiska Christydira Sekaringtyas

Dear Rob Keller ,

Thank you very much.

I would like to ask for a bit more detail regarding the calculation.

If I want to make a final lipid concentration of 25 mg/mL, how do I calculate the weight of each component?

Thank you in advance.

Best regards.

Rob Keller

Dear Fransiska Christydira Sekaringtyas

Since the give ratios are molar ratios, you cannot calculate the necessary grams directly, you need to work with mol first. Well, this obviously can be performed in various ways, but if I finish my example:

5.66/1000 x 790.2 mg/mL = 4.47 mg/mL (would render 5.66 mM DSPC)

2.87/1000 x 744.034 mg/mL = 2,14 mg/mL (would render 2.87 mM DOPE)

1.47/1000 x 2790.521 mg/mL = 4,10 mg/mL (would render 1.47 mM PEG2000-DSPE)

This would end up in a lipid concentration of 10,71 mg/mL. So, multiplying all the above concentrations with 25/10.71 renders: 10,43 mg DSPC, 5,00 mg DOPE and 9,57 mg PEG2000-DSPE and this dissolved in 1 mL will give you a lipid concentration of 25 mg/mL.

Best regards.

Fransiska Christydira Sekaringtyas

Dear Rob Keller ,

Ok, well-noted.

Thank you very much for your detailed explanation. It really helps me to have a well understand to calculate amounts of lipid for preparing liposomes.

Best regards.

How to calculate Z (the number of molecules in a unit cell) for calculating theoretical density?

How to get/count refractive index in gasses?

What is the reason film thickness increased?

Want to ask about equivalence ratio?

How doping in nano-particles with same valency affect it's crystal lattice structure?

Any resist stripper which can remove thick metal based polymer residue and which is compatible with doped silicon ?

In Michaelis-Menten Kinetics, why K(subscript)On have units (mol^-1)(time^-1)?

Is it possible to detect oxPAPC in the serum?

Are there any molecular dynamics sofware easy to use for homo lumo interraction in molecular dynamics or some sofware for magnetic interraction spins?

Do chemical and physical properties influence on the size of a polymer particle?