Synthesis of Brushite Particles in Reverse Microemulsions of the Biosurfactant Surfactin

Department of Earth and Environmental Sciences National Chung Cheng University, 168 University Road, Min-Hsiung, Chia-Yi 62102, Taiwan
International Journal of Molecular Sciences (Impact Factor: 2.86). 12/2011; 12(6):3821-30. DOI: 10.3390/ijms12063821
Source: PubMed


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.

Download full-text


Available from: Jyoti Prakash Maity,
  • Source
    • "The particles were reported to be homogeneous in size and were stable over a period of 2 months. Maity et al. (2011) synthesized crystalline calcium pyrophosphate nanoparticles of different morphologies by varying the water-to-surfactant (W/S) ratio in water/hexane/Surfactin reverse-microemulsion system. Nanoparticles with size distribution of 50–500 nm were obtained when the as-synthesized noncalcinated calcium phosphate (synthesized at room temperature) particles were subjected to calcination at a temperature of 800°C. "

    Biosurfactants: Research Trends and Applications, Edited by Catherine N. Mulligan, Sanjay K. Sharma, Ackmez Mudhoo, 01/2014: pages 221-234; CRC Press., ISBN: ISBN 9781466518230
  • [Show abstract] [Hide abstract]
    ABSTRACT: Calcium phosphate powders were synthesized based on a wet chemical precipitation method at room temperature. A critical aging time of the precipitate is required in order to form a desired intermediate complex that permits a further transformation to apatite phase under appropriate thermal treatment. The processing parameters effect on apatite formation was systematically studied in terms of aging time and different condition of synthesis using Thermal Analysis, X-ray diffraction and Fourier transform infrared spectroscopy. The transformation of calcium phosphate deficient apatite (monetite and Ca 2P 2O 7) obtained after one and two weeks of aging time into hydroxyapatite is completed when a heat treatment is applied at 600 °C under air. The HA nanocrystal sizes decrease with the increase of the aging periods, from 90 to 50 nm. The results show that by suitable tailoring of the processing parameters one can obtain calcium phosphate powders of desired dimensions.
    Studia Universitatis Babeș-Bolyai. Chemia 09/2011; STUDIA UBB CHEMIA, 2011, LVI, 3, 147 – 156. · 0.19 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Chemical precipitation followed by hydrothermal processing is conventionally employed in the laboratory-scale synthesis of hydroxyapatite (HAp) and extensive information on its processing conditions has therefore been provided in literature. However, the knowledge about the influence of some operating parameters, especially those important for a large-scale production, is yet insufficient. A specific approach based on a Taguchi orthogonal array was therefore used to evaluate these parameters and to optimize them for a more effective synthesis. This approach allowed us to systematically determine the correlation between the operating factors and the powder quality. Analysis of signal-to-noise ratios revealed the great influence of temperature and pH on the characteristic of powder. Additionally, the injection rate of one reagent into another was found to be the most important operating factor affecting the stoichiometric ratio of powders. As-prepared powders were also studied for their in-vitro bioactivity. The SEM images showed the accumulation of a new apatite-like phase on surface of the powder along with an interesting morphological change after a 45-day incubation of powder in SBF, indicating a promising bioactivity. Some results also showed the capability of simple hydrothermal method for the synthesis of a lamellar structure without the help of any templating system.
    Journal of Crystal Growth 12/2012; 361(1):73–84. DOI:10.1016/j.jcrysgro.2012.09.010 · 1.70 Impact Factor
Show more