Biomedical applications of silica-based aerogels: a comprehensive review

Silica-based aerogels are the appropriate and well-known porous materials that have become interesting in science and technology, especially in the biomedical community. Silica-based aerogels are prepared from silica gels where the liquid is drawn out of the network structure so that its three-dimensional structure is not disturbed. From a nanotechnologist's perspective, silica aerogels will have a special place in nanotechnology because they have low density, large surface area and nanometer pores, and the size of their pores can be adjusted in different ways. In addition to their prominent features, these materials are very attractive despite the possibility of changing their chemical composition according to the desired applications. Recent advances in silica-based aerogels as well-known porous materials have had a great impact on extensive application in various fields mostly in high-tech science and engineering, and biomedical usages, including environmental control, tissue engineering, cancer diagnosis, cancer therapy, biomarking, and drug delivery. Many vital and key issues in the field of (nano) material applications, especially their usages in biomedicine, should be investigated before clinical applications. Some of these important issues include toxicity, bioactivity, compatibility, and so on. Minimal toxicity and maximum biodegradability are two important future challenging issues related to the interaction of (nano) materials and biological systems. So, it is essential to know how to design and synthesize nanoscale structures for medical and biological applications. Engaging with materials whose characteristics can be customized is very important in the medical field. In this review, we intend to provide up-to-date information on silica-based aerogels and applications in biomedicine. Hence, this review summarizes biomedical applications of silica-based aerogels and discusses the potential toxicity induced by them. The present study focuses on the basic concepts and recent advances in silica-based aerogels in the biomedical field.