Nanobiotechnology for health-care

A novel Zn(II) complex loaded solid lipid nanoparticles for breast cancer treatment: Synthesis, characterization and cytotoxic studies
Guney Eskiler G.1, Cecener G.2, Kani I.3, Dikmen G.4, Egeli U.2, Tunca B.2
1 Medical Biology Department, University of Sakarya, Sakarya, Turkey. 
E-mail: gamzeguney@sakarya.edu.tr
2 Medical Biology Department, University of Uludag, Bursa, Turkey.
3 Chemistry Department, University of Anadolu, Eskisehir, Turkey.
4 Central Research Laboratory Application and Research Center (ARUM), University of Eskisehir Osmangazi, Eskisehir, Turkey.

Zinc (Zn) plays an important role in a wide range of cellular processes including cell proliferation, differentiation and apoptosis etc. However, they indicate unspecific toxicity to healthy cells [1]. Solid lipid nanoparticles (SLNs) provide unique features including small size, low toxicity and controlled drug release [2]. For this purpose, we synthesized a novel Zn(II) complex with diphenyl acetic acid and 2-2’-bipyridyl ligands, [Zn(C6H5)2CHCOO)(bipy)2](bipy)(ClO4) and produced Zn (II) complex-SLNs formulation by hot homogenization and characterized by Nano-Zeta Sizer. Furthermore, the in vitro cytotoxic and apoptotic effects of Zn(II) complex and Zn(II)-SLNs formulation (1-10 µM) were examined on breast cancer (MCF7) and human umbilical vein endothelial (HUVEC) cell line. 
The MCF7 cell viability decreased to 12.8% and 35.5% while, the cell viability of HUVEC reduced to 52.30% and 79.4% after treatment with 10 µM of Zn(II) complex and Zn(II)-SLNs for 48 h (p<0.05), respectively. A total apoptotic death rate of MCF7 and HUVEC cells was 69.5% and 16.4%, at 10 µM Zn(II)-SLNs, respectively. Consequently, Zn(II) complex indicated considerable cytotoxic effects on MCF-7 and HUVEC cells. However, Zn(II)-SLNs reduced toxic effects of Zn(II) complex in HUVEC control cells and induced apoptosis in MCF-7 cells. Thus, SLNs are promising drug delivery system to minimize undesirable side-effects of metal-based complexes and provide therapeutic activity for cancer treatment.
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