Evaluation of Commercial Latex as a Positive Control for In Vitro Testing of Bioceramics

Abstract:

Several tests for the biological evaluation of bioceramic materials and medical devices are provided in specific international standards, where in vitro tests have a major role. Tests involving exposure of cells in culture require the use of validated positive controls, which, in the same preparation and treatment conditions, present a substantial and well-known cytotoxicity. The present work aimed to test and validate 3 different sources of low cost, commercially available latex, as positive controls in cytotoxicity tests for bioceramic materials performed by indirect exposure. The tested origins for latex samples were: surgical gloves without powder, 100% pure amber latex hospital-grade tourniquets and 60 % latex White tubing. MC3T3-E1 murine pre-osteoblasts in culture were exposed to conditioned media (extracts) of each material tested, along with sintered stoichiometric hydroxyapatite bioceramics, and polystyrene beads as negative control. Cell viability was determined by XTT and Crystal Violet Exclusion tests. Concentration curves of the extracts were performed to obtain the DC₅₀. Only the 100% pure amber latex tubing was proven to be cytotoxic, with cell survival less than 5%. This material did not affected neighboring groups at the same experimental system. Moreover, latex samples showed great repeatability in different tests against latex and biomaterials, with consistent toxicity under 20% cell survival as shown in 3 different cell viability parameters. We conclude that fragments of latex ambar tubing are suited as effective positive controls in tests of medical bioceramic materials.

• Periodical: Key Engineering Materials (Volume 631)
• Pages: 357-362
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.631.357
• Online since: November 2014
• Authors: Emanuelle Stellet Lourenço, Juliana Côrtes, Joyce Costa, Adriana Linhares, Gutemberg Alves
• Keywords: Cytotoxicity, Latex, Medical Devices, Positive Control, Surgical Supplies

References

[1] International Organization for Standardization. ISO 10993-5: Biological evaluation of medical devices-Part 5: Tests for in vitro cytotoxicity (2009) ISO 10993-5: (2009).

DOI: 10.2345/9781570203558

[2] W. S. Stokes. Best practices for the use of animals in toxicological research and testing. Ann. NY Acad. Sci. (2011) 1245: 17-20.

[3] OECD, 2010. Guidance Document on Using Cytotoxicity Tests to Estimate Starting Doses for Acute Oral Systemic Toxicity Tests (N. 129). Available in http: /iccvam. niehs. nih. gov/SuppDocs/FedDocs/OECD/OECD-GD129. pdf.

[4] M. Hanson, & D. Lobner. In vitro neuronal cytotoxicity of latex and nonlatex orthodontic elastics. Am J Orthod Dentofacial Orthop 126 (2004) 65-70.

DOI: 10.1016/j.ajodo.2003.07.006

[5] M. Kobayashi, T. W. Tsutsui, T. Kobayashi, M. Ohno, Y. Higo, T. Inaba, T. Tsutsui. Sensitivity of human dental pulp cells to eighteen chemical agents used for endodontic treatments in dentistry. Odontology, 101(1) (2013) 43-51.

DOI: 10.1007/s10266-011-0047-9

[6] M. N. Vidal, C. Aiub, S. Abrantes, , & H. P. Zamith. Evaluation of Brazilian medical devices using agar diffusion cytotoxicity assay, Rev. Bras. Hematol. Hemoter. 31(2) (2009) 84-87.

DOI: 10.1590/s1516-84842009000200009

[7] S. O. Rogeroa, T. I. Ikedab, A. S. Cruzb. Teste in vitro de Citotoxicidade: Estudo Comparativo entre Duas Metodologias, Mat. Res. 6(3) (2003) 317-320.

DOI: 10.1590/s1516-14392003000300003

[8] C. Zhang, , N. Zhang & X. Wen. Improving the elasticity and cytophilicity of biodegradable polyurethane by changing chain extender, J Biomed Mater Res B Appl Biomater 79 (2006) 335-344.

DOI: 10.1002/jbm.b.30547

[9] G. De-Deus, A. Canabarro, G. Alves, A. Linhares, M. I. Senne & J. M. Granjeiro. Optimal cytocompatibility of a bioceramic nanoparticulate cement in primary human mesenchymal cells, J. Endod. 35(10) (2009) 1387-1390.

DOI: 10.1016/j.joen.2009.06.022

[10] H. S. Baek, J. Y Yoo, D. K. Rah, D. W. Han, D. H. Lee, O. H. Kwon, & J. C. Park. Evaluation of the extraction method for the cytotoxicity testing of latex gloves, Yonsei Med J. 46(4) (2005) 579-583.

DOI: 10.3349/ymj.2005.46.4.579