Modulating Physicochemical Features of Mesoporous Strontium Silicate Nanostructures: A Design of Experiments Approach

Mesoporous silicate nanoparticles are known for pore size, pore volume, high surface area, and tunable surface properties and as a result, have found application in medicine, healthcare, advanced materials, and devices. Furthermore, tailoring the silicate domain with certain metals has advanced the tissue engineering properties by moderating the cellular function at the molecular level for therapeutic response. However, scarce efforts have been made to explore systemic methods that could change the structure and shape of these particles and their effects on biological properties. Here, we have focused on, using Design of Experiments (DoE), optimizing reaction conditions for the synthesis of mesoporous strontium silicate nanostructures (NS) (nanoparticles – NPs and nanorods – NRs) with different physico-chemical properties. The conditions allowed change in shape from NPs to NRs by tailoring the concentration of liquid ammonia (NH4OH, 82.7 mM to 248.2 mM) during the pre-synthesis incubation state. In addition, the optimized reaction conditions allowed modulating the physico-chemical properties such as surface area, surface charge, amount of metal, pore diameter, pore volume, tailored degradation profile and release profile of the loaded drug (gentamicin). Finally, the protocol has the advantage of allowing incorporation of other metals such as cerium, rhodium, and ruthenium independently and/or in combination.