Biocompatible Silver Nanoparticle-Modified Natural Diatomite with Anti-Infective Property

Abstract

Nanosilver as an alternative antibacterial agent of antibiotics has been researched for possible applications in various orthopedic implants. However, it is imperative to achieve controllable release of Ag+ to reduce its cytotoxic effect on normal tissue. Here, a nanosilver release system that has potential to be used in anti-infective bone cement was reported. Nanosilver modified diatomite was developed through the reaction of Tollens’ reagent to improve the antibacterial effect and natural diatomite was used as the carrier of Ag+ ions for controlled release. Cytotoxicity and the antibacterial activities of the nanosilver release system were characterized. After 3 days, the NIH3T3 cells cultured in the extract of nanosilver modified diatomite with an initial concentration of 0.5 mg/ml showed better cell viability than cells cultured in α-MEM. The density of MC3T3-E1 cells cultured in the extract of nanosilver modified diatomite at the same concentration did not differ significantly from the density of cells cultured in α-MEM. The nanosilver modified diatomite exhibited antibacterial effect against E. coli and S. aureus when the concentration was higher than 0.5 mg/ml. With appropriate selection of Ag+ concentration, the nanosilver modified diatomite is promising for improving the antibacterial effect while not affecting the biocompatibility of reinforced calcium phosphate bone cement.

A Green Method for Synthesis of Silver-Nanoparticles-Diatomite (AgNPs-D) Composite from Pineapple (<i>Ananas comosus</i>) Leaf Extract

“…The composite was then added with a carboxymethyl cellulose solution followed by calcination at 400 °C [21]. Besides, the researchers used chemicals such as sodium borohydride solution [22], hydrogen peroxide [23], and Tollens' reagent [24][25] to produce AgNPs. However, some of these methods are not environmentally friendly and expensive because they use high calcination temperatures and toxic reducing agents.…”

Nanotechnology-enabled materials for hemostatic and anti-infection treatments in orthopedic surgery

“…104,105 In another example, nanosilver modified diatomite (AgDT) has been developed by depositing silver nanoparticles uniformly on the surface of natural diatomite disk, achieving a prolonged and uniform release of Ag + . 106 Then, AgDT with a proper nanosilver concentration revealed excellent antibacterial effects against both Escherichia coli and Staphylococcus aureus without significant cytotoxicity to fibroblasts and osteoblasts. 106 Nanoparticles also have the potential for drug delivery applications in orthopedics.…”

“…106 Then, AgDT with a proper nanosilver concentration revealed excellent antibacterial effects against both Escherichia coli and Staphylococcus aureus without significant cytotoxicity to fibroblasts and osteoblasts. 106 Nanoparticles also have the potential for drug delivery applications in orthopedics. 107,108 Antimicrobial nanoparticles can be engineered into scaffolds for tissue regeneration purpose.…”

Natural Diatom Biosilica as Microshuttles in Drug Delivery Systems

“…They outlined the increased drug loading and release properties of diatoms after acid and peroxide treatments, which increased silanol groups at the diatoms surface, thus increasing the percentage of drug encapsulation (or drug loading (DL) wt%) from 0.47 to 9.47 wt%. More recently, Sun et al produced nanosilver-modified diatomite (nAgDT) by directly mixing in situ silver ions with ammonia solution, pure diatomite, Tollen’s reagent, and glucose [61]. The well-loaded nanosilver particles (3.08 wt% of silver in the nAgDT) were equally distributed on the diatomite (Figure 4).…”

“…Corresponding energy-dispersive X-ray spectroscopy (EDS) results are shown in ( a , b ). Reproduced from [61], copyright (2018), Hindawi, licensed under CC BY 4.0.…”