Nanostructured material formulated acrylic bone cements with enhanced drug release
Shou-Cang Shen1, Wai Kiong Ng1, Yuan-Cai Dong1
1Institute of Chemical and Engineering Sciences, A*STAR (Agency for Science, Technology and Research), 1 Pesek Road, Jurong Island, Singapore 627833, Singapore.
Summary
Poly(methyl methacrylate) bone cements enhanced with nanostructured materials improve antibiotic delivery. Mesoporous silica nanoparticles (MSN) offer superior gentamicin release and mechanical properties compared to hydroxyapatite and carbon nanotubes.
Area of Science:
- Biomaterials Science
- Nanotechnology
- Drug Delivery Systems
Background:
- Poly(methyl methacrylate) (PMMA) bone cements are crucial in orthopedic surgery.
- Improving antibiotic elution from bone cement is essential for preventing infections.
- Nanostructured materials are explored as carriers to enhance drug release and maintain mechanical integrity.
Purpose of the Study:
- To evaluate the efficacy of different nanostructured materials (hydroxyapatite nanorods, carbon nanotubes, mesoporous silica nanoparticles) as drug carriers for gentamicin in PMMA bone cements.
- To investigate the impact of these nanocarriers on both drug release kinetics and mechanical properties of the bone cement.
- To explore the potential of a binary delivery system using mesoporous silica nanoparticles.
Main Methods:
- Formulation of PMMA-based bone cements with varying concentrations of hydroxyapatite nanorods, carbon nanotubes, and mesoporous silica nanoparticles.
- Incorporation of gentamicin (GTMC) as the model antibiotic.
- Assessment of gentamicin release profiles over 80 days.
- Evaluation of the mechanical properties of the formulated bone cements.
- Investigation of a dual-drug delivery system utilizing mesoporous silica nanoparticles.
Main Results:
- Hydroxyapatite nanorods below 10% showed limited gentamicin release improvement; higher content negatively impacted mechanical properties.
- Carbon nanotubes enhanced gentamicin release significantly (75% in 80 days at 5.3%), but severely compromised mechanical strength.
- Mesoporous silica nanoparticles demonstrated effective gentamicin delivery with well-preserved mechanical properties.
- Hollow nanostructured materials facilitate sustained drug release by forming nano-networks for diffusion.
Conclusions:
- Mesoporous silica nanoparticles are promising nanocarriers for gentamicin in PMMA bone cements, balancing enhanced drug delivery and mechanical stability.
- The nanostructure of carriers plays a critical role in achieving sustained antibiotic release.
- Binary delivery systems based on MSN offer potential for co-delivery of multiple antibiotics.
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