This study describes the development of a novel method of three dimensional perfused cell culture for in vitro toxicity testing. Multiple parallel perfused microbioreactors (TissueFlex^TM) were adopted to provide a well-controlled cell culture environment. Alginate and collagen type I, commonly used as hydrogel scaffolds to support cell culture, were tested as the scaffolding materials for this application. Alginate supports cell proliferation, but does not support cell attachmen...