Preparation Procedure of Liposome-Absorbed Substrate and Tip Shape Correction of Diameters of Liposome Measured by AFM

Yuichi Muraji, Takaya Fujita, Hiroshi Itoh, Daisuke Fujita

Advanced Key Technologies Division, National Institute for Materials Science (NIMS), Tsukuba, Japan.
Research Institute of Instrumentation Frontier, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba, Japan;.
Surface Analysis Laboratories, Toray Research Center Inc. (TRC), Otsu, Japan;.

DOI: 10.4236/mr.2013.13005                

Abstract

The procedure to measure liposome in aqueous solution has been examined using atomic force microscope (AFM). We concluded a chemical modified silicon wafer (substrate for AFM observation of liposome) with 3-aminopropyltrieth-oxysilane (APTES) which enabled us to scan anionic liposome softly in water because they were keeping structures as vesicles and stably adsorbed on the substrate by electrostatic force. From captured AFM topographic images, we counted the amount of liposome and analyzed the distribution of mean diameters, which were corrected by an approximated curve of the tip shape. We discussed the method of effective evaluation as practical analysis and its problems for robust analysis.

Keywords

Atomic Force Microscope (AFM); Dynamic Light Scattering (DLS); Anionic Liposome; 3-Aminopropyltriethoxysilane (APTES)

Conflicts of Interest

The authors declare no conflicts of interest.

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