Development of micro-CT for living cells applying scanning probe microscopy

2002 Fiscal Year Final Research Report Summary

• Project/Area Number: 12558116
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Single-year Grants
• Section: 展開研究
• Research Field: Biomedical engineering/Biological material science
• Research Institution: Kagoshima National College of Technology
• Principal Investigator: SUDA Takao Kagoshima National College of Technology, Department of Electrical Engineering, Professor, 電気工学科, 教授 (10163031)
• Co-Investigator(Kenkyū-buntansha): MIYATA Chikara Kagoshima National College of Technology, Department of Electronic Control Engineering, Professor, 電子制御工学科, 助教授 (80229864) ; IKEDA Hideyuki Kagoshima National College of Technology, Department of Mechanical Engineering, Professor, 機械工学科, 教授 (80113413) ; AKAZAWA Shoji Kagoshima National College of Technology, Department of Electrical Engineering, Professor, 電気工学科, 教授 (40141965)
• Project Period (FY): 2000 – 2002
• Keywords: Scanning Probe Microscopy / Magnetic Force Microscopy / Electrical Conductivity / Electrical impedance / Erythrocytes

Research Abstract

The purpose of this study is to develop the method of three-dimensional (3-D) imaging of the inner structure of living cells applying scanning probe microscopy. The possibility of magnetic resonance force microscopy (MRFM) applied to scanning probe microscopy (SPM) was investigated for 3-D imaging. The method of composing a 3-D image by the computer processing based on the data of the surface shape and local electric conductivity measured with SPM was also examined. The sensitivity of the usual magnetic force microscope (MFM) was estimated to apply for the method of detecting of magnetic change by resonance absorption. It is clear that realizing a 3-D imaging system by MRFM using the usual MFM is difficult because of the low sensitivity, which is able to detect the set including more than 1000 paramagnetic iron ions. On the other hand, for the method using local electric conductivity measured with SPM, we tried to fabricate a conductive probe that covered insulator except the tip. Two kinds of fabrication methods were examined, which a resin was applied over the conductive cantilever except the tip and a conductive silicon cantilever oxidized, and etched only at the tip. At present, the probe that can be used for the measurement is not obtained in each method. Then, the method using AC impedance instead of DC conductivity that applied non-contact AFM was examined. It succeeded in the measurement of the surface potential of a red blood cell in atmosphere, which is an important step to the impedance measurement. The simulation has been also investigated using the model that surrounding electrolyte, the cell membrane and the cytoplasm are assumed to be simple infinite layers and spherical body with different electric conductivity is buried in the cytoplasm layer.