Evaluación de carácter adhesivo de un hidrogel antimicrobiano en pericardio bovino

Abstract

[EN] Current satellite tags used to study migration patterns of whales have a short service life due to poor biocompatibility. After its deployment, tag retention time is not long enough to provide valuable data. In order to improve its service life, the design of a certain type of satellite tag, called Type-C tag, is being modified through a project lead by the National Oceanic and Atmospheric Administration (NOAA) partnering with the Engineered Biomaterials Laboratory at Michigan Technological University. One of the modifications that will be made consists on the application of an antimicrobial coating to the tag’s surface, to reduce bacterial colonization, increase its adhesiveness to the tissue and eventually improve tag retention times. In the present project the adhesive character of a hydrogel that could be used as a potential coating is evaluated through an experiment performed in standard bovine pericardium tissue. Four different types of hydrogels have been evaluated: three of them composed of polydopamine nanoparticles, fibrinogen and thrombin, and differentiated by the mixing order of its components during the preparation; and a fourth control hydrogel formed by fibrinogen and thrombin. The adhesiveness of the hydrogels to the tissue has been assessed through a single lap shear testing, simulating the shearing forces that the tag can suffer as the animal swims. Analyzing the data, the maximum force reached in every type of hydrogel has been obtained. A statistical analysis has shown that there is a significant difference between the different types of polydopamine hydrogels, although none of them showed a significant difference with the control. The mixing order of the components that allows the best adhesion to the tissue has been determined.

[ES] El objetivo del proyecto es evaluar el carácter adhesivo de un hidrogel antimicrobiano utilizado para mejorar la biocompatibilidad de dispositivos de telemetría por satélite de grandes cetáceos. Para ello se ha llevado a cabo un experimento sobre tejido estándar de pericardio bovino. Sobre el mismo se han evaluado tres tipos distintos de hidrogel compuestos por nanopartículas de polidopamina (PDA), fibrinógeno y trombina, y diferenciados entre sí por el orden de mezcla de los componentes durante la preparación. Además, para evaluar el efecto de la PDA se ha preparado un hidrogel control formado únicamente por fibrinógeno y trombina. La adhesividad de los hidrogeles al tejido ha sido evaluada mediante un test mecánico de tracción, simulando así las fuerzas de tracción y cizalla a las que estaría sometido el dispositivo de telemetría mientras el animal nada. Mediante el análisis de los datos se ha obtenido la máxima fuerza soportada por cada tipo de hidrogel. Realizando análisis estadístico se ha probado que existe una diferencia significativa entre el hidrogel control y los hidrogeles preparados con PDA, así como entre los distintos tipos de hidrogeles de PDA. Se ha podido determinar el orden de mezcla de componentes del hidrogel que permite una mayor adhesividad al tejido.

[EN] The objective of the project is to evaluate the adhesive character of antimicrobial hydrogels used to increase the biocompatibility of satellite telemetry tags in large cetaceans. An experiment was designed and performed on a standard tissue sample of bovine pericardium. Three different type of hydrogels were evaluated, composed of polydopamine nanoparticles (PDA), fibrinogen and thrombine, and differentiated by the mixing order of its components during the preparation. In order to evaluate the effect of the PDA nanoparticles a control hydrogel composed only of fibrinogen and thrombine has been prepared. The adhesiveness of the hydrogel to the tissue has been evaluated through a mechanical testing, simulating the shearing forces which the tag can suffer as the animal swims. Analyzing the data the maximum force reached in every type of hydrogel was obtained. A statistical analysis has shown that there is a significant difference between the control hydrogel and the hydrogels prepared with PDA, as well as between the different type of PDA hydrogels. The mixing order of the components that allows the best adhesion to the tissue has been determined.