Microcirculation system with a dialysis part for bioassays evaluating anticancer activity and retention.

Medicines are distributed to the whole body and excreted over time. A micromodel of the circulation-excretion system was developed to mimic these processes. This system comprised a dialysis part, a microperistaltic pump, and a target tissue. This microcirculation system was created on a microchip composed of a glass slide and polydimethylsiloxane sheets with microchannels fabricated by photolithography. A dialysis membrane was settled between two channels to form the dialysis part, and a pneumatic peristaltic pump was used to make the solution flow. The excretion and half-life of solute substances absorbed to albumin were changed according to their affinity to the protein. MCF-7 human breast cancer cells were cultured as target cells for drug samples, and the activities of anticancer agents were assayed using our system. Our data demonstrated that the anticancer activity of docetaxel or thio-TEPA could be assayed on the microcirculation-excretion chip. This system may allow for reduced consumption of cells and reagents compared to those required for conventional in vitro bioassay systems.