• targeted drug delivery;
  • ovarian cancer;
  • cytotoxicity;
  • microspheres


The 3-(4,5 dimethylthiazol-2-yl)-2,5 diphenyltetrazolium bromide (MTT) assay is used successfully to estimate the number of viable cells in drug screening trials. We used the MTT assay to assess the viability of a rodent ovarian carcinoma cell line (DMBA-OC-1R) after exposure to combinations of cisplatin and 5-fluorouracil as free drug and in encapsulated (conjugated and unconjugated) forms. After 48h of exposure to free drugs, a significant trend towards cell cytotoxicity could be observed and this was well established by 120h. Cells treated with drug-containing immuno-microspheres showed a similar initial decrease in cell viability after 96h, and this was maintained for 128h. These results suggest that immuno-microspheres loaded with chemotherapeutic drugs have the potential to be successfully used in the treatment of ovarian cancer.