Kinetic oxygen measurements by CVC96 in L-929 cell cultures

A recent challenge to bone and cartilage tissue engineering is to lift up research-scale products to a level of reproducible tissue substitute fabrication that is clinically effective, e.g. by the use of bioreactors [1,2]. Bioreactors can be considered as devices in which biological and/or biochemical processes are performed under controlled conditions (e.g. pH, temperature, pressure, oxygen supply, nutrient supply and waste removal). Most of the bioreactors were initially developed to test biomaterials [3]. The survival of cells in vivo as well as in bioreactors depends on the response of the distinct cells to the environment. A higher oxygen tension for example is needed for osteoblastic differentiation, whereas prolonged hypoxia favours formation of cartilage or fibrous tissue [4]. The adjustment of oxygen tension in bioreactors is therefore a critical aspect in bioreactor design. The simplest and most widely used bioreactor for bone and cartilage tissue engineering today is indeed the culture dish [5]. Animal and human cells use oxygen during their whole life. Consequently the oxygen use is a simple indicator to test the vitality of cells.Vitality and cytotoxicity tests are established techniques in different fields such as cell culture control, search of active agents and also in other medical techniques. To the broad field of medical technology belongs also the testing of biocompatibility in the field of development and examination of tooth- and bone replacement tissues in cranio-maxilliofacial surgery. The research group for biomineralization and tissue engineering of this department carries out the testing of biocompatibility.Up to now the temporal course of cell reactions on toxic influences could be observed only with a high input of labor time (and costs). Because of this high input we have tested the new measuring technology CVC96 with a short test in practical applications. CVC96 allows the possibility to observe and evaluate cell tests also kinetically