Asymmetric membrane capsules for osmotic drug delivery II. In vitro and in vivo drug release performance.

In a previous paper, we described asymmetric membrane capsules and a phase inversion process for manufacturing them. In this paper, we describe the in vitro and in vivo drug release characteristics from these capsules. The capsule formulations were developed with model drugs to understand the variables that influenced drug release. Studies were also conducted to understand the drug release mechanism and it was shown that osmotic drug delivery was possible with asymmetric membrane capsules.