T1 In situ investigation of the cytotoxic and interfacial characteristics of titanium when galvanically coupled with magnesium using scanning electrochemical microscopy
A1 Souto, Ricardo Manuel
A1 Asserghine, Abdelilah
A1 Ashrafi, Amir M.
A1 Mukherjee, Atripan
A1 Petrlak, Frantisek
A1 Heger, Zbynek
A1 Svec, Pavel
A1 Richtera, Lukas
A1 Nagy, Lívia
A1 Nagy, Géza
A1 Adam, Vojtech
A2 Química
A2 Departamento de Química
Grupo de Electroquímica y Corrosión
Instituto de Materiales y Nanotecnología
K1 titanium
K1 magnesium
K1 galvanic coupling
K1 local electrochemical activity
K1 cytotoxic effects
K1 pH variations
K1 reactive oxygen species
AB Recently, the cytotoxic properties of galvanically coupled Mg-Ti particles have been shown todifferent cells, although this cytotoxic effect has been attributed mainly to Mg due to itstendency to undergo activation when coupled with Ti forming a galvanic cell consisting of ananode (Mg) and a cathode (Ti). However, the role of the Ti cathode has been ignored inexplaining the cytotoxic effect of Mg-Ti particles due to its high resistance to corrosion. In thiswork, the role of titanium (Ti) in the cytotoxic mechanism of galvanically coupled Mg-Tiparticles was examined. A model galvanic cell was prepared to simulate the Mg-Ti particles.The electrochemical reactivity of the Ti sample and the pH change above it due to galvaniccoupling with Mg were investigated using scanning electrochemical microscopy (SECM). Itwas observed that the Ti surface changed from passive to electrochemically active whencoupled with Mg. Furthermore, after only 15 min galvanic coupling with Mg, the pH in theelectrolyte volume adjacent to the Ti surface increased to an alkaline pH value. The effects ofthe galvanic coupling of Ti and Mg, as well as of the alkaline pH environment, on the viabilityof Hs27 fibroblast cells were investigated. It was shown that the viability of Hs27 cellssignificantly diminished when Mg and Ti were galvanically coupled compared to when the twometals were electrically disconnected. Next, the generation of reactive oxygen species (ROS)increased when the Ti and Mg were galvanically coupled. Thus, although Ti usually exhibitedhigh corrosion resistance when exposed to physiological environments, an electrochemicallyactive surface was observed when galvanically coupled with Mg, and this surface mayparticipate in electron transfer reactions with chemical species in the neighboring environment;this participation resulted in the increased pH values above its surface and enhanced generationof ROS. These features contributed to the development of cytotoxic effects by galvanicallycoupled Mg-Ti particles.
LK http://riull.ull.es/xmlui/handle/915/25284
UL http://riull.ull.es/xmlui/handle/915/25284
LA en
DS Repositorio institucional de la Universidad de La Laguna
RD 24-nov-2024