Faculty Advisor

Rulfs, Jill


Demand for autologous cartilage for reconstructive surgery and structural repair necessitated by injury and disease such as osteoarthritis is very high. Due to the low yield of cartilage from primary patient harvests, primary explant cartilage must be augmented by tissue engineering techniques to meet this demand. The use of polyglycolic acid (PGA) and poly-l-lactic acid (PLLA) as scaffold materials to localize cells and promote focal matrix accumulation has shown much promise. Based on previous studies that demonstrated chondrocyte metabolism is dependent upon interstitial pH, concerns have been raised on the use of biodegradable polymers that produce acidic fragments. The growth of chondrocytes on PGA matrices has been augmented by the use of flow bioreactors, which increase transport of nutrients to and waste away from cells. A flow velocity of 1 [mu]m/s directed through the culturing tissue has been engineered to optimize pH maintenance between 6.9 to 7.2, which has been suggested to stimulate cartilage matrix biosynthesis. The objectives of this study were to 1) characterize ECM assembly by chondrocytes on PLLA/PGA scaffolds in static culture and a perfusion bioreactor, 2) assess the relative roles of cell metabolism and polymer degradation in regulating environmental pH in both static and bioreactor culture, and 3) explore the effects of varying concentrations of PLLA on cell adhesion.


Worcester Polytechnic Institute

Date Accepted

January 1999



Project Type

Major Qualifying Project


Restricted-WPI community only

Advisor Department

Biology and Biotechnology