Pharmaceutical Research

, Volume 15, Issue 11, pp 1721–1726 | Cite as

Visualization of PEO-PBLA-Pyrene Polymeric Micelles by Atomic Force Microscopy

  • Jiahorng Liaw
  • Takao Aoyagi
  • Kazunori Kataoka
  • Yasuhisa Sakurai
  • Teruo Okano
Article

Abstract

Purpose. To directly visualize and evaluate the aqueous block copolymeric micelles, poly(ethylene oxide)-poly(β-benzyl L-aspartate) (PEO-PBLA) chemically conjugated with pyrene fluorescence molecule, by nanotechnology of atomic force microscopy (AFM).

Methods. The block copolymers' PEO-PBLA-Pyrene was first synthesized by reacting with pyrene sulfonyl chloride and PEO-PBLA in tetrahydrofuran (THF) solution and were identified by GPC reflect index, UV and fluorescence detectors. The characterization of physical and chemical properties of PEO-PBLA-Pyrene polymeric micellar solution were examined by the dynamic light scattering (DLS) and critical micelles concentrations (CMC). In addition, the nanotechnology of AFM was used to directly visualize the size and shape of nanopolymeric micelles.

Results. The pyrene fluorescence molecule were successfully conjugated at the amino group of the end of PBLA chain by GPC with three different detectors. The size of the aqueous PEO-PBLA-Pyrene polymeric micelles was detected around 57 nm with unimodal distribution by DLS measurement. As a result of this finding, the CMC test was also found out that the fluorescence intensity was increasing around 0.01 ∼ 0.05 mg/ml. Using AFM evaluation of polymeric micellar solution, the morphology of aqueous PEO-PBLA-Pyrene polymeric micelles was observed on round shape and with the narrow dispersity of size range 50 ∼ 80 nm.

Conclusions. The presence of PEO-PBLA copolymers with pyrene in an aqueous system formed in a spherical and nano range of polymeric micelles.

polymeric micelles AFM DLS pyrene 

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

REFERENCES

  1. 1.
    J. S. Hrkach, M. T. Peracchia, A. Domb, N. Lotan, and R. Langer. Nanotechnology for biomaterials engineering: structural characterization of amphiphilic polymeric nanoparticles by 1H NMR spectroscopy. Biomaterials 8:27–30 (1997).Google Scholar
  2. 2.
    S. E. Dunn, G. A. Coombes, M. C. Garnett, S. S. Davis, M. C. Davies, and L. Illum. In vitro cell interaction and in vivo biodistribution of poly(lactideco-glycolide) nanospheres surface modified by poloxamer and poloxamine copolymers. J. Contr. Rel. 44:65–76 (1997).Google Scholar
  3. 3.
    M. Yokoyama, M Miyauchi, N. Yamada, T. Okano, Y. Sakurai, K. Kataoka, and S. Inoue. Characterization and anticancer activity of the micelle-forming polymeric anticancer drug adriamycin-conjugated poly(ethylene glycol)-poly(asparatic acid) block copolymer. Cancer Res. 50:1693–1700 (1990).Google Scholar
  4. 4.
    G. Kwon, S. Suwa, M. Yokoyama, T. Okano, Y. Sakurai, and K. Kataoka. Enhanced tumor accumulation and prolonged circulation times of micelle-forming poly(ethylene oxide-asparate) block copolymer-adriamycin conjugates. J. Contr. Rel. 29:17–23 (1994).Google Scholar
  5. 5.
    S. Zalipsky. Chemistry of polyethylene glycol conjugates with biologically active molecules. Adv. Drug Delivery Rev. 15:157–182 (1995).Google Scholar
  6. 6.
    G. S. Kwon, M. Natio, M. Yokoyama, T. Okano, Y. Sakurai, and K. Kataoka. Physical entrapment of adriamycin in AB block copolymer micelles. Pharm. Res. 12:192–195 (1995).Google Scholar
  7. 7.
    G. Kwon, M. Natio, M. Yokoyama, T. Okano, Y. Sakurai, and K. Kataoka. Micelles based on AB block copolymers of poly(ethylene oxide) and poly(b-benzyl L-aspartate). Langmuir 9:945–949 (1993).Google Scholar
  8. 8.
    S. A. Hagan, G. A. Coombes, M. C. Garnett, S. E. Dunn, M. C. Davies, L. Illum, S. S. Davis, S. E. Harding, S. Purkiss, and P. R. Gellert. Poly(lacatide)-poly(ethylene glycol) copolymers as drug delivery systems. 1. characterization of water dispersible micelle forming systems. Langmuir 12:2153–2161 (1996).Google Scholar
  9. 9.
    A. P. Quist, A. Petersson, C. T. Reimann, A. A. Bergman, D. D. N. Barlo Daya, A. Hallen, S.O. Oscarsson, and B. Sundqvist. Site-selective molecular adsorption at nanometer scale MeV atomic ion induced surface defects. J. Coll. Interface Sci. 189:184–187 (1997).Google Scholar

Copyright information

© Plenum Publishing Corporation 1998

Authors and Affiliations

  • Jiahorng Liaw
    • 1
  • Takao Aoyagi
    • 2
  • Kazunori Kataoka
    • 3
  • Yasuhisa Sakurai
    • 2
  • Teruo Okano
    • 2
  1. 1.Department of Pharmaceutics, School of PharmacyTaipei Medical CollegeTaipeiTaiwan
  2. 2.Institute of Biomedical EngineeringTokyo Women's Medical UniversityShinjuku, TokyoJapan
  3. 3.Department of Material Science, Graduate School of EngineeringThe University of TokyoBunkyo-ku, TokyoJapan

Personalised recommendations