Microgel Translocation through Pores under Confinement

Non-affinity factors modulating vascular targeting of nano- and microcarriers

“…Recent studies show that flexible gel particles with minimal cross-linking translocate through barrier materials with pores tenfold smaller than nanogel diameter under pressures resembling those experienced during renal filtration (Figure 2a). Flexible NIPAm particles of ~1100nm and ~850nm diameter passed through pores of 100nm diameter at levels commensurate with those observed for 88nm polystyrene beads [89,90] (Figure 2b). Alternative nanogels of 116nm diameter also passed through 10nm pores where 88nm polystyrene beads did not [89,91].…”

How does a polymer chain pass through a cylindrical pore under an elongational flow field?

“…To our knowledge, the experimental investigation of microgel translocation through cylindrical pores under biologically relevant pressure differentials was first reported by Lyon et al [55], where two well-defined microgels made of N-isopropylacrylamide (NIPAM) and acrylic acid (AA, 10 mol%) with a similar size but different pH-dependent compressibilities were prepared to investigate the generality of the translocation phenomenon (Fig. 11).…”

“…(A) Schematic illustration of filtration setup and microgel filtration through a track-etch membrane; and (B) Filtration comparison of microgels with degrees of cross-linking of 1% and 3% mol, 88 nm polystyrene, and 200 nm polystyrene particles (0.01 wt %) (reported by Lyon et al[55]). Reproduced with permission[55].…”

Transmission behavior of pNIPAM microgel particles through porous membranes

“…Microgels are flexible spheres which can undergo changes in both size and elasticity in response to changes in temperature, ionic strength, and pH [16]. Some previous studies have shown that microgels can deform quite significantly under shear, leading to their translocation through nanoporous structures [13][14][15]. When soft microgel slurries are subjected to shear, their microstructure is altered [17], and this affects their colloidal stability, often leading to shear-induced aggregation [18].…”

“…While there have been some reports on the deformability of microgels in nanopores, these studies have looked at the phenomenon from the point of view of renal elimination, i.e. transport through glomerular membrane [13][14][15].…”