The Goldilocks Effect
Standard diffusion is driven by concentration gradients: when a high concentration solution is exposed to a lower concentration solution, molecules diffuse more quickly at first, in a burst, slowing as the concentration gradient reduces and the system comes to equilibrium. Unlike standard diffusion, nanoscale constrained diffusion does not exhibit concentration-driven kinetics. When molecules encounter pores that are slightly larger than the molecules themselves, diffusion is limited by the pore size. Molecules are forced to move through the pores only one at a time, producing linear release kinetics until the device is nearly empty.
The Pore Is Too Small
No Molecules Can Escape
When the pore size is smaller than the molecule itself, the molecule does not exit through the pore.
Poor Delivery Profile
No medication is delivered.
The Pore is Too Big
Molecules Exit Too Fast Too Soon
When the pore size is sufficiently large that molecules freely diffuse through the membrane, the rate of delivery decreases as the concentration equilibrates.
Typical delivery profile of current treatments
Medication is delivered at an uneven rate, potentially creating unnecessary side effects and limiting efficacy.
The Pore is “Just Right”
Molecules Leave at an Even Pace
When the pore size matches that of the molecule, constrained diffusion produces constant-rate release even as the concentration equilibrates across the membrane.
Optimal delivery profile
Medication is delivered at an even rate that eliminates concentration variability, potentially minimizing side effects and maximizing efficacy of treatment.
Visualize the Molecular Release
A Tale Of Two Pores
Tunable pore size makes drug delivery “just right”
NanoPortal incorporates a proprietary technique that enables nanometer-scale tuning to achieve pore sizes as small or large as necessary to produce constant release.