Devices and methods for delivering therapeutics

A method treating of delivering a first molecule to a subject, the method comprising:

• implanting an implantable device in the subject;
• controlling diffusion of at least the first molecule and a second molecule across a porous polymeric membrane of the implantable device at least partially encapsulating a population of human cells, wherein said population of human cells comprises at least one selected from the group of human pancreatic progenitor cells, human endocrine cells, human alpha cells, human delta cells, and human beta cells,
• wherein the membrane includes a plurality of open pores, wherein the membrane has an average pore size equal to or less than 1 μm, wherein the membrane has an average thickness of between 10 μm and 150 μm,
• wherein a ratio of Dfirst/Dsecond is equal to or greater than 2 and less than or equal to 50, wherein Dfirst is a first diffusion coefficient across the membrane for the first molecule having a first molecular weight between or equal to 50 Da and 10 kDa, wherein Dsecond is a second diffusion coefficient across the membrane for the second molecule having a second molecular weight between or equal to 50 kDa and 500 kDa, and wherein a ratio of said second molecular weight to said first molecular weight is equal to or greater than 10.

A method of delivering a first molecule to a subject, the method comprising:

• implanting an implantable device in the subject;
• controlling diffusion of at least the first molecule and a second molecule across a porous crosslinked electrospun polymeric membrane of the implantable device at least partially encapsulating a population of cells,
• wherein the membrane includes a plurality of open pores, wherein the membrane has an average pore size equal to or less than 1 μm, wherein the membrane has an average thickness of between 10 μm and 150 μm,
• wherein a ratio of Dfirst/Dsecond is equal to or greater than 2 and less than or equal to 50, wherein Dfirst is a first diffusion coefficient across the membrane for the first molecule having a first molecular weight between or equal to 50 Da and 10 kDa, wherein Dsecond is a second diffusion coefficient across the membrane for the second molecule having a second molecular weight between or equal to 50 kDa and 500 kDa, and wherein a ratio of said second molecular weight to said first molecular weight is equal to or greater than 10.