Sterilization of biological tissue with ozone

• Grant number: 19/22907-4
• Support type: Research Grants - Innovative Research in Small Business - PIPE
• Duration: November 01, 2020 - July 31, 2021
• Field of knowledge: Engineering - Biomedical Engineering - Medical Engineering
• Principal researcher: Sílvia Móbille Awoyama
• Grantee: Sílvia Móbille Awoyama
• Company: Silvia Mobille Awoyama
• CNAE: Atividades de serviços de complementação diagnóstica e terapêutica
• City: Pindamonhangaba
• Assoc. researchers: Carlos José de Lima ; Milene da Silva Melo ; Renato Amaro Zângaro ; Terezinha de Jesus Andreoli Pinto ; Túlia de Souza Botelho Almeida

Abstract

The amniotic membrane (AM) has been employed in burns and wound healing (to reduce surface inflammation, scarring and pain in surgical applications), and in oral, maxillofacial and ocular surface surgeries. Therefore, it is sterilization is a relevant process for application as biomaterial. Justification: Currently, one of the main techniques available for this process is gamma radiation, which in the standard dosage for sterilization can generate morphological and structural changes in AM, particularly regarding basement membrane disintegration, fine collagen fiber decomposition, chromatin condensation. and lead to a significant decrease in growth factors. Thus, it is imperative to develop new technologies that aim to sterilize biological tissues and involve lower operational risks, cost reduction, without environmental contamination and without inducing significant changes in biological tissues. Ozone (O3) can be considered the most potent natural germicide in existence and is capable of eliminating viruses, bacteria, protozoa and fungi with high efficiency and speed due to it is highly oxidizing activity. Goals: The aim of this work is to evaluate the effectiveness and applicability of the human amniotic membrane sterilization process using a closed hydrodynamic circuit for the transfer of medicinal oxygen-water and ozone-water mass from an injector. Venturi. Methodology: The amniotic membrane will be collected as determined by the Technical Standards for the functioning of umbilical and placental cord blood banks according to Resolution - RDC No. 190 of July 18, 2003. The samples will be fractionated into pieces measuring 5 cm2, these will be experimentally contaminated with Staphylococcus aureus (106 CFU/mL), Escherichia coli (106 CFU/mL), Candida albicans (106 CFU/mL), Staphylococcus epidermidis (106 CFU/mL), spores of Clostridium sporogenes (106 CFU/mL), endotoxins and submitted to quantitative and qualitative microbiological analysis before and after the application of ozone. In addition, histological analysis, scanning and transmission electron microscopy will be performed to verify that the morphological and ultrastructural characteristics of the tissue were preserved after the procedure. Expected results: In microbiological analyzes, ozone is expected to promote sterilization and pyrogenicity of AM. In addition, it is believed that the procedure employed does not induce significant morphological and ultrastructural changes in the evaluated tissue. (AU)