Lipid Geometry Tool

Phospholipid Inventory

Estimate how many lipids sit in the outer and inner leaflets of a unilamellar particle from simple membrane geometry, editable lipid areas, and an ideal random-mixing composition model.

Outer vs inner leaflet counts Editable multi-lipid mixture Single-particle mol% spread

Geometry

Assumptions

Particle outer diameter

Bilayer thickness

Distribution shown for

The current model treats the entered diameter as the outer headgroup diameter of a single-bilayer vesicle and assumes symmetric leaflet composition.

Summary

Live totals

Average area per lipid 0.65 nm^2

Outer leaflet headgroups 0

Inner leaflet headgroups 0

Total headgroups 0

Model Note

Statistics

The composition spread is modeled as ideal random mixing on a finite number of lipid slots, so the per-particle count of a chosen lipid is treated as binomial. Real liposome preparations can be broader because of size polydispersity, formulation history, and non-ideal mixing.

Composition Table

The last row auto-balances the mixture so total composition stays at 100 mol%. Literature presets fill the area-per-headgroup value with approximate published fluid-phase values.

Color	Show	Name	mol%	Headgroup / area	Outer	Inner	Total

Reference Vesicle

Sampled view

Colored headgroups are sampled from the current composition and shown symmetrically on the outer and inner leaflets.

Composition Distribution

Ideal random mixing

Mean expected mol% 0%

Standard deviation 0%

Typical 68% range 0%

Typical 95% range 0%

Particle lipid slots used for distribution 0

Probability of exact target mol% n/a

Probability within ±0.5 mol% n/a

Probability within ±1.0 mol% n/a