Synthesis of Brushite Particles in Reverse Microemulsions of the Biosurfactant Surfactin

• Main Authors: Young-Fo Chang, Hau-Ren Chen, Chien-Cheng Chen, A. Satyanarayana Reddy, Shashi B. Atla, Henry Pai-Heng Cheng, Chien-Yen Chen, Tz-Jiun Lin, Jyoti Prakash Maity
• Format: Article
• Language: English
• Published: MDPI AG 2011-06-01
• Series: International Journal of Molecular Sciences
• Subjects: biosurfactant; reverse microemulsion; brushite; surfactin; nanoparticle
• Online Access: http://www.mdpi.com/1422-0067/12/6/3821/

In this study the “green chemistry” use of the biosurfactant surfactin for the synthesis of calcium phosphate using the reverse microemulsion technique was demonstrated. Calcium phosphates are bioactive materials that are a major constituent of human teeth and bone tissue. A reverse microemulsion technique with surfactin was used to produce nanocrystalline brushite particles. Structural diversity (analyzed by SEM and TEM) resulted from different water to surfactin ratios (W/S; 250, 500, 1000 and 40,000). The particle sizes were found to be in the 16–200 nm range. Morphological variety was observed in the as-synthesized microemulsions, which consisted of nanospheres (~16 nm in diameter) and needle-like (8–14 nm in diameter and 80–100 nm in length) noncalcinated particles. However, the calcinated products included nanospheres (50–200 nm in diameter), oval (~300 nm in diameter) and nanorod (200–400 nm in length) particles. FTIR and XRD analysis confirmed the formation of brushite nanoparticles in the as-synthesized products, while calcium pyrophosphate was produced after calcination. These results indicate that the reverse microemulsion technique using surfactin is a green process suitable for the synthesis of nanoparticles.