Controlling liquid–liquid phase behaviour with an active fluid

Vorticity phase separation and defect lattices in the isotropic phase of active liquid crystals

“…The combination of eqn (4b) and ( 5) implies that the relaxation rate of vorticity fluctuations is determined by the same dispersion relation that controls C > , given by eqn (8). Expanding the mode for q { l Z À1 gives a simple linear equation commonly seen in models of pattern-formation, q t ô = iO 4 (q) ô, with iO 4 (q) = À[t c À1 + k 2 q 2 + k 4 q 4 ] +O(q 6 ), (11) where k 2 = K/g + l(a + al)/(2G) and k 4 = (ÀaZl + KGl 2 À aZl 2 )/ (2G 2 ), both depend on activity. Such an equation has been used as a minimal model to study emergent structures and dynamics in active fluids, where it has been shown to support various time-independent solutions in the form of vortex lattices 34 when k 2 o 0.…”

“…It has been quantified in active liquid crystals of cytoskeletal microtubule bundles cross-linked by kinesins, motor proteins that consume ATP as they move along the bundles, creating extensile stresses on the flow in which they are submerged. 4–8 Active liquid crystals have been studied extensively through continuum theories, and there is now a large body of analytical and numerical work characterizing their stability, dynamical regimes and interactions with other immiscible species. 9–16…”

“…It has been quantified in active liquid crystals of cytoskeletal microtubule bundles cross-linked by kinesins, motor proteins that consume ATP as they move along the bundles, creating extensile stresses on the flow in which they are submerged. [4][5][6][7][8] Active liquid crystals have been studied extensively through continuum theories, and there is now a large body of analytical and numerical work characterizing their stability, dynamical regimes and interactions with other immiscible species. [9][10][11][12][13][14][15][16] Controlling this chaotic spontaneous flow to create coherent structures holds the promise of engineering active fluids for microfluidic applications and functional materials capable of delivering directed mechanical forces.…”

“…[9][10][11][12][13][14][15][16] Controlling this chaotic spontaneous flow to create coherent structures holds the promise of engineering active fluids for microfluidic applications and functional materials capable of delivering directed mechanical forces. 17 Active liquid crystals have become promising candidates for these applications, 6,8 as physical confinement, substrate friction and substrate patterning allow control of chaotic flow and development of coherent structures. These effects have been mainly examined so far in regimes of parameters corresponding to the ordered nematic state of the passive liquid crystal.…”

Understanding and fine tuning the propensity of ATP-driven liquid–liquid phase separation with oligolysine

“…As a consensus has been reached that the principles governing biomolecular phase separation should guide the development of innovative liquid-based organelles and therapeutics, numerous studies addressing the tunable predisposition to LLPS and fibrillization and controllable pathway and dynamics of liquid condensates have been reported. 24–30 To manipulate the amyloidogenic pathway, chimeric peptides merging highly amyloidogenic fragment of insulin's A-chain 31,32 with oligolysine were proposed. With the addition of ATP, such amyloidogenic pathway could be altered by varying the length of oligolysine.…”