Toward Highly Dispersed Mesoporous Bioactive Glass Nanoparticles With High Cu Concentration Using Cu/Ascorbic Acid Complex as Precursor

Abstract

Copper (Cu) ions have a variety of advantageous biological functionalities, such as proangiogenic and bactericidal activities. Given the intrinsic biodegradability and biocompatibility, silicate-based mesoporous bioactive glass nanoparticles (MBGNs) are considered as promising platforms for the delivery of Cu ions. However, effective incorporation of Cu into MBGNs still faces challenges, e.g., particle aggregation, the formation of insoluble crystalline Cu-based nanoparticles, and a low loading amount of Cu. We report a novel method to synthesize chemically homogenous and highly dispersed Cu-containing MBGNs (Cu-MBGNs) with tunable Cu concentration by using ascorbic acid/Cu complexes as the precursor of Cu in a microemulsion-assisted sol-gel approach. Cu-MBGNs exhibited a sphere-like shape with a particle size between 100 and 300 nm while their pore size varied from 2 to 10 nm. The inclusion of Cu, regardless of the incorporated concentration, did not significantly affect the morphology of particles. ICP-AES results indicated that the concentration of Cu in the particles could be conveniently tuned from 0 to ~6 mol% by controlling the amount of ascorbic acid/Cu complexes added, while the formation of crystalline Cu-based nanoparticles was avoided. The amorphous feature of Cu-MBGNs was proved by XRD, while the predominant oxidation state of Cu was evidenced to be Cu 2+ by XPS. The incorporation of Cu did not inhibit the apatite-forming ability (bioactivity) of the particles in contact with simulated body fluid. Cu-MBGNs exhibited the capability of releasing Cu, Si, and Ca ions over time in the physiological fluid. The concentration of released Cu ions could be controlled by selecting specific Cu-MBGNs of different Cu contents. The dissolution products of most Cu-MBGNs at the dosage of 1, 0.1, and 0.01 mg/mL did not exhibit cytotoxicity, while only 7Cu-MBGN was cytotoxic at the dosage of 1 mg/mL. This study provided a feasible strategy to synthesize highly dispersed amorphous Cu-MBGNs with high Cu concentrations for biomedical applications. The particles exhibit great potential as building blocks for developing composite 3D scaffolds, coatings, and drug carriers, particularly when a large amount of particles incorporated may compromise the properties of (polymer) matrix materials while a relatively high concentration of released Cu ions is still required.

Strontium- and Cobalt-Doped Multicomponent Mesoporous Bioactive Glasses (MBGs) for Potential Use in Bone Tissue Engineering Applications

“…As shown in Figure 5B, zeta potential of the MBGs changes from 5 mV for Ca-MBG group (parent glass) to −16, −6, −12 mV for Sr-, Co-, and Sr-Co-MBG groups, respectively. A similar phenomenon was reported elsewhere for Cu-doped MBGs [42]: the increased zeta potential values may be related to the elevated amounts of positively charged ions in MBGs structure as well as the quick release of the dopants used. It has been previously reported that the surface charge of MBGs have significant effects from a biological viewpoint [43][44][45].…”

Hybrid gelatin/oxidized chondroitin sulfate hydrogels incorporating bioactive glass nanoparticles with enhanced mechanical properties, mineralization, and osteogenic differentiation

“…S2a ) shows the sphere-like shape of the particles with a particle size of ~100 nm. The morphology of MBGNs was in good agreement with that of mesoporous silicate nanoparticles synthesized using similar methods [ 20 , 23 ]. The mesoporous structure, large specific surface area and pore volume of MBGNs have been confirmed in our previous study [ 20 ].…”

“…The morphology of MBGNs was in good agreement with that of mesoporous silicate nanoparticles synthesized using similar methods [ 20 , 23 ]. The mesoporous structure, large specific surface area and pore volume of MBGNs have been confirmed in our previous study [ 20 ]. The morphological characteristics of MBGNs were expected to enhance the dispersion in polymeric matrices and interactions with polymeric molecules towards a more integrated structure [ 13 , 24 ].…”

“…MBGNs were synthesized as described in previous studies [ 20 , 21 ]. Briefly, 2.80 g CTAB was dissolved in 132 mL deionized water under stirring at 35 °C.…”

Nanotherapeutics for regeneration of degenerated tissue infected by bacteria through the multiple delivery of bioactive ions and growth factor with antibacterial/angiogenic and osteogenic/odontogenic capacity

“…Adding to this, the mesoporous nanoparticle form of bioactive glass has the capacity to intracellular deliver therapeutic molecules (drugs, growth factors, or genes) [ 16 ]. Some of the recent studies have reported that mesoporous bioactive glass nanomaterials and their composites/hybrids could demonstrate the capacity for delivering drugs and genes, as well as releasing bioactive ions [ [18] , [19] , [20] , [21] , [22] , [23] , [24] , [25] , [26] , [27] , [28] , [29] , [30] ].…”