Current status and outlook of biodegradable metals in neuroscience and their potential applications as cerebral vascular stent materials

Abstract

Over the past two decades, biodegradable metals (BMs) have emerged as promising materials to fabricate temporary biomedical devices, with the purpose of avoiding potential side effects of permanent implants. In this review, we first surveyed the current status of BMs in neuroscience, and briefly summarized the representative stents for treating vascular stenosis. Then, inspired by the convincing clinical evidence on the in vivo safety of Mg alloys as cardiovascular stents, we analyzed the possibility of producing biodegradable cerebrovascular Mg alloy stents for treating ischemic stroke. For these novel applications, some key factors should also be considered in designing BM brain stents, including the anatomic features of the cerebral vasculature, hemodynamic influences, neuro-cytocompatibility and selection of alloying elements. This work may provide insights into the future design and fabrication of BM neurological devices, especially for brain stents.

A Complex In Vitro Degradation Study on Polydioxanone Biliary Stents during a Clinically Relevant Period with the Focus on Raman Spectroscopy Validation

“…The use of stents made of these materials, among other benefits, eliminates the need for further invasive procedures [ 7 , 8 , 9 ]. For clinical use of biodegradable stents, the stent must be able to support the tissue for a defined period and subsequently degrade at an appropriate rate [ 10 ]. For this reason, it is necessary to sufficiently describe the degradation process of these materials.…”

Advances in Bioresorbable Triboelectric Nanogenerators

“…(A) Environment-specific biodegradation processes of metals based on their reaction with body fluid. Reproduced with permission from ref . Copyright 2019 Elsevier.…”

“…Furthermore, it is required to identify how the device components are absorbed and eliminated in the body. One representative approach to follow their elimination pathway utilizes ICP-MS to detect residual amounts of metallic elements within biological tissues during device degradation . Finally, verifying that the electrical energy generated does not adversely affect biological systems is necessary.…”

Effect of Mg Addition and PMMA Coating on the Biodegradation Behaviour of Extruded Zn Material

“…It is essential to control the degradation of the metallic biomaterial in order to avoid problems with local alkalization. It can cause haemolysis of the red blood cells and high metallic ion release, which results in low cell viability and the rapid loss of mechanical strength before the biomaterial can fulfil its supporting function [ 9 , 10 ]. Phosphate conversion coating, biomimetic deposition of Ca- and P-rich layers, organic and polymer coating, anodic oxidation, micro-arc oxidation, atomic layer deposition of different metallic oxides, magnetron sputtering of carbon films, and sandblasting were all discussed for a more controlled biodegradation behaviour of Zn-based materials [ 11 ].…”