Cyto- and genotoxicity evaluation of the biomedical polyesters obtained in the presence of new zinc catalytic systems

ABSTRACT

A preliminary evaluation of cyto- and genotoxicity of the biomedical polyesters obtained in the presence of new zinc catalytic systems was performed. A series of biomedical poly(ε-caprolactone)s (PCLs) and poly(rac-lactide)s (PLAs) synthesized in the presence of diethylzinc/propyl gallate or diethylzinc/gallic acid catalytic systems were tested using the luminescent bacterium Vibrio fischeri, the ciliated protozoan Spirostomum ambiguum as well as Salmonella typhimurium TA1535. The main goal of our work was to find the correlation between the zinc catalyst content in the synthesized products and cyto- or genotoxicity of the synthesized polyesters or their degradation products. To remove the metal catalyst residue, the obtained polyesters were subjected to the purification procedure. The Zn content in the synthesized polymers was determined by flame atomic absorption spectrometry. It was found that the purified PCLs and PLAs which contained the Zn below ca. 450 ppm were not cyto- or genotoxic. Importantly, the Zn content in the synthesized PCLs and PLAs after the second polymer precipitation was significantly reduced to 14 ppm. We believe that our results are satisfactory enough for the biomedical applications, i.e., for the synthesis of biomedical polyesters used as drug delivery systems.

GRAPHICAL ABSTRACT

KEYWORDS:

• Biomedical polyesters
• cytotoxicity
• flame atomic absorption spectrometry
• genotoxicity
• poly(ε-caprolactone)
• polylactide

Acknowledgments

The authors would like to thank Andrzej Jaklewicz from the Medical University of Warsaw for the technical support. The authors are indebted to Andrzej Plichta (Warsaw University of Technology) for the GPC measurements and Monika Pisklak and Violetta Kowalska (Medical University of Warsaw) for the spectroscopy measurements.