Biological Use of Nanostructured Silica-Based Materials Functionalized with Metallodrugs: The Spanish Perspective

Abstract

Since the pioneering work of Vallet-Regí’s group on the design and synthesis of mesoporous silica-based materials with therapeutic applications, during the last 15 years, the potential use of mesoporous silica nanostructured materials as drug delivery vehicles has been extensively explored. The versatility of these materials allows the design of a wide variety of platforms that can incorporate numerous agents of interest (fluorophores, proteins, drugs, etc.) in a single scaffold. However, the use of these systems loaded with metallodrugs as cytotoxic agents against different diseases and with distinct therapeutic targets has been studied to a much lesser extent. This review will focus on the work carried out in this field, highlighting both the pioneering and recent contributions of Spanish groups that have synthesized a wide variety of systems based on titanium, tin, ruthenium, copper and silver complexes supported onto nanostructured silica. In addition, this article will also discuss the importance of the structural features of the systems for evaluating and modulating their therapeutic properties. Finally, the most interesting results obtained in the study of the potential therapeutic application of these metallodrug-functionalized silica-based materials against cancer and bacteria will be described, paying special attention to preclinical trials in vivo.

Amino acid‐decorated mesoporous silica nanoparticles loaded with titanocene derivatives for targeted anticancer studies

“…In summary, considering the good stability of the systems in solution, which do not release metal-containing species as confirmed by the absence of signals of titanium species in the DNA-binding studies, which validate the action of these materials as non-classical drug-delivery systems, 39 these results confirm the stability of the materials as well as their selectivity, which is why it has great potential to carry out future in vivo trials and could be a great step for new treatments based on chemotherapy. 40 Four novel metallodrug functionalized nanostructured materials incorporating four different amino acids, MSN-AP-Cys-Ti, MSN-AP-Cap-Ti, MSN-AP-Pen-Ti, and MSN-AP-Met-Ti, have been prepared and characterized.…”

Melatonin Derivative-Conjugated Formulations of Pd(II) and Pt(II) Thiazoline Complexes on Mesoporous Silica to Enhance Cytotoxicity and Apoptosis against HeLa Cells

“…Silica nanoparticles have several beneficial properties that make them perfect candidates for drug delivery such as suitable biodegradability, biocompatibility, mesoporous structure for high drug loading and chemical and mechanical stability [ 4 , 5 ]. The incorporation of metal complexes in this type of nanoparticulate systems allows us to solve most of the disadvantages associated with the use of free metal complexes, improving their bioavailability [ 6 , 7 ].…”

Organotin(IV)‐Decorated Graphene Quantum Dots as Dual Platform for Molecular Imaging and Treatment of Triple Negative Breast Cancer

“…[24,25] However, it was not until recently when the strong therapeutic potential of organotin(IV) compounds loaded in nanostructured and mesoporous silica nanoparticles has been demonstrated by our group both in vitro and in vivo. [26][27][28][29][30][31][32] In this regard, carbon dots (CDs) are an ideal nanomaterial to create a vehicle that can simultaneously enable bioimaging, disease detection, and drug delivery. [33] CDs are rising stars in the carbon family and nanomedicine, due to their excellent properties, such as biocompatibility, water solubility, low cytotoxicity, low-cost production and tunable fluorescence.…”

“…For instance, nanoparticles created via ultrasonic irradiation containing organotin(IV) complexes have been prepared previously in two isolated studies [24,25] . However, it was not until recently when the strong therapeutic potential of organotin(IV) compounds loaded in nanostructured and mesoporous silica nanoparticles has been demonstrated by our group both in vitro and in vivo [26–32] …”