Silica-based matrices: State of the art and new perspectives for therapeutic drug delivery.

Colloidal carriers based on silica (Si) matrices are an innovative approach within the context of therapeutic drug delivery systems. These carriers are emerging as a great promise for diagnosis and treatment of a wide range of injuries, particularly in cancer and infectious diseases. In addition, bioencapsulation for biosensing and cell therapy in silica sol-gel allows the survival of enzymes and cells for a long period of time. Owing to their porosity, large surface area, and high capability of functionalization, silica nanoparticles (SiNP) have been considered as an attractive option for several bioanalysis applications, such as selective bioseparation, imaging, and drug and gene delivery. However, although great advances are achieved in the biomedical fields, some toxicity effects can be associated with the use of SiNP. This article aims to present a comprehensive review of recent technological advances for silica matrices in biomedical applications, as well as the potential impact of silica-based materials on human health and environment.