Scaffold based on castor oil as an osteoconductive matrix in bone repair: biocompatibility analysis

Fabianne Soares Lima,Isnayra Kerolaynne Pacheco,Walter Moura,Josué Junior Araujo Pierote,Luis Felipe Matos,Alessandra Ribeiro,Ana Cristina Fialho,José Milton Matos,Fernando Reis,João Victor Frazão Câmara

doi:10.1590/0104-1428.210018

Abstract

To analyze the biocompatibility of the scaffold produced from a natural polymer derived from castor oil through hemolytic activity and antimicrobial activity, to enable the clinical application. Three in vitro tests were performed: Hemolytic activity test - Polymer partially dissolved in contact with blood agar; Hemolytic activity test in sheep's blood - Polymer extract with red blood cells solution; Antimicrobial activity test - Solid polymer in direct contact with E. Coli and S. Aureus. For hemolytic tests, none of the samples showed hemolysis. Negative hemolytic activity is a good indicator, as the maintenance of the blood clot in the area of the lesion is essential for the formation of new tissue. For the antimicrobial activity test, no significant activity was observed against the bacteria used. The polymer is not toxic to red blood cells, being viable for clinical application as a matrix for tissue regeneration.

Highlights

There is a vast amount of surgical procedures performed in an attempt to repair bone tissue damaged by disease or trauma
This study aims to analyze the biocompatibility of the castor oil scaffold, with the main tests of toxic activity against red blood cells and antimicrobial activity, to enable the clinical application of this biomaterial as an osteoconductive matrix in the repair of bone injuries
The reagents used in the production of monoacylglycerides (MAG) and its polymer (CPU) were glycerol (C3H8O3, Impex), lithium hydroxide (LiOH, Vetec), and Hexamethylene Diisocyanate (HDI) (C8H12N2O2, Sigma-Aldrich) for polymerization[7]

Summary

Introduction

There is a vast amount of surgical procedures performed in an attempt to repair bone tissue damaged by disease or trauma. The field of tissue engineering research aims to develop biological substitutes that restore, maintain or improve the function of damaged tissue by combining body cells with biomaterials. Commonly produced from polymeric biomaterials, provide structural support for cell binding and subsequent tissue development[1]. Scaffolds produced from various biomaterials are used in the field in an attempt to regenerate different tissues and organs in the body. Regardless of the type of fabric, a number of considerations are important when designing or determining the suitability of scaffold for use in tissue engineering, this generally requires that the devices be equivalent in performance, biocompatibility, safety, stability and sterility to previously approved devices[2]. The characteristics that biomaterials must have are: a) biocompatibility: the material must be non-toxic, not promote an acute or chronic inflammation reaction, have a low tissue reactivity, that is, do not promote host rejection; b) bioabsorption: the material must have degradability that will accompany the formation of a new tissue; c) porosity: the material must have a pore density of around 75% with average sizes of 200 to 400 mm in diameter, to favor protein adhesion, in addition to increasing the collagen formation; d) chemotaxis: the material must attract mesenchymal cells and provide means of cell adhesion, facilitating cell proliferation and differentiation; e) angiogenesis: the material must promote vascularization, being hydrophilic, to absorb blood fluid and reinforce the initial coagulation after implantation; f) low cost: the material cannot exceed the value of the autograft, having abundant constituent materials and efficient sterilization[3,4,5]

Objectives

Methods

Results