STM images of PDLLA-PEG copolymer micelles

Hadi M. Zareie, Xu Kaitian, Erhan Pişkin

Research output: Contribution to journalArticle

8 Scopus citations

Abstract

Poly(DL-lactic acid)-poly(ethylene glycol) (PDLLA-PEG) copolymers with micelle-forming abilities were produced by transesterification of PDLLA (Mn = 1866) prepared in this study with PEG (Mn = 3300-4000). Micelles of these copolymers were formed in aqueous media. Critical micelle concentrations were determined spectrophotometrically. Average values of molecular mass and diameter of the micelles were determined by light scattering. Scanning electron microscopy (SEM) photographs of micelles were obtained for comparison. Scanning tunneling microscopy (STM) images of these micelles on highly oriented pyrolytic graphite surfaces were also obtained. STM was operated in air at atmospheric pressure with a tip-to-substrate bias of 500 mV and tunnelling currents of < 100 pA, and in the constant current mode. The micelle sizes obtained by STM were of the same order, but larger than those determined from light scattering data and those obtained by SEM.

Original languageEnglish (US)
Pages (from-to)19-24
Number of pages6
JournalColloids and Surfaces A: Physicochemical and Engineering Aspects
Volume112
Issue number1
DOIs
Publication statusPublished - Jul 1 1996

    Fingerprint

All Science Journal Classification (ASJC) codes

  • Surfaces and Interfaces
  • Physical and Theoretical Chemistry
  • Colloid and Surface Chemistry

Cite this