Incorporating DNA in a lamellar phase: a Flory model

Area of Science:

• Soft Matter Physics
• Materials Science
• Biophysics

Background:

• Experimental studies show DNA incorporation into neutral lamellar phases.
• Understanding particle behavior in lyotropic liquid crystal phases is crucial.

Purpose of the Study:

• To theoretically model the incorporation of finite-size rod-like particles into lyotropic smectic-A phases.
• To predict phase behavior and coexistence in ternary systems (rods/water/surfactant).

Main Methods:

• A Flory-type lattice model was employed.
• A ternary phase diagram was calculated.

Main Results:

• The model predicts particle incorporation into smectic-A phases with interlamellar spacing smaller than rod length.
• Coexistence of particle-enriched and particle-depleted lamellar phases is demonstrated.
• Rod-like particles in the depleted phase exhibit nematic-like orientational order.

Conclusions:

• Theoretical predictions align qualitatively with experimental observations.
• The model provides insights into the self-assembly of rod-like particles in liquid crystal phases.