RT Journal Article SR Electronic T1 Role of the Pharmaceutical Excipients in the Tamoxifen Activity on MCF-7 and Vero Cell Cultures JF Anticancer Research JO Anticancer Res FD International Institute of Anticancer Research SP 4529 OP 4533 VO 29 IS 11 A1 ROSSI, TIZIANA A1 IANNUCCELLI, VALENTINA A1 COPPI, GILBERTO A1 BRUNI, ELISA A1 BAGGIO, GIOSUÉ YR 2009 UL http://ar.iiarjournals.org/content/29/11/4529.abstract AB Background: Microparticles are used for controlled drug delivery. With the aim of improving both bioavailability and tamoxifen selective toxicity, the activity of tamoxifen embedded in calcium alginate/chitosan microparticles was studied. Materials and Methods: Tamoxifen alone and embedded in microparticles prepared with sodium alginate from Kelco (62% mannuronic acid and 38% guluronic acid) and from Fluka (30% mannuronic acid and 70% guluronic acid) was added to MCF-7 and Vero cultures and evaluated for antiproliferative activity by the MTT test. Results: The use of Kelco or Fluka alginate resulted in different LD50 values on Vero and MCF-7 cultures, showing a higher cytotoxicity toward Vero cells treated with tamoxifen embedded in Kelco microparticles (25 μM vs. 48 μM on MCF-7 cells) but a selective toxicity with Fluka microparticles (25 μM and 10 μM on Vero and MCF-7 cells respectively). Conclusion: Microparticle formulation may improve selective toxicity according to the alginate employed: differences in the chemical alginate composition can dramatically change both drug activity and toxicity.