From melt-derived to nanocomposite glasses: A brief history of magnetic bioactive glass-ceramics applied in magnetic hyperthermia

The application of hyperthermia principles to heat tumors dates back to 2600 B.C., and its progress has been closely tied to advancements in physics and materials science. However, the concept of magnetic hyperthermia emerged only in the 1950s, based on iron oxide colloids. In 1970, the first magnetic bioactive glass-ceramic was introduced into biomaterials, as these materials could combine bone cancer treatment with the regeneration of damaged bone tissue. Since then, numerous advances have been made to enhance both i) hyperthermia therapy through improvements in magnetic properties and ii) bone regeneration by enhancing bioactivity. In this review, we illustrate the challenges of integrating both properties into a single material and how advancements in glass and glass-ceramic and composite engineering processing technology have helped overcome this hurdle, focusing on the magnetic properties, bioactivity, and specific absorption rate (SAR) of each processing method. Briefly, the history of magnetic bioactive glass-ceramics can be categorized into three generations related to specific glass processing technologies: the 1st generation consists of glass-ceramics produced by melt-quenching followed by crystallization; the 2nd generation includes biphasic ceramics composites made from magnetic glass-ceramics obtained through melt-quenching and another phase comprised of sol-gel-derived bioactive glass; the 3rd generation is based on glass-ceramics produced entirely by the sol-gel method, resulting in composites or nanocomposites. Finally, we discuss the emerging 4th generation based on nanoengineered heterostructures and offer future perspectives for those interested in contributing to further advancements in magnetic hyperthermia derived from bioactive glass-ceramic materials and their composites.