AVS 53rd International Symposium
    Applied Surface Science Thursday Sessions
       Session AS-ThP

Paper AS-ThP3
High Resolution Mass Spectrometric Analysis of Non-Dehydrated Biological Samples

Thursday, November 16, 2006, 5:30 pm, Room 3rd Floor Lobby

Session: Aspects of Applied Surface Science Poster Session
Presenter: H.F. Arlinghaus, Universit@um a@t M@um u@nster, Germany
Authors: H.F. Arlinghaus, Universit@um a@t M@um u@nster, Germany
J. M@um o@ller, Universit@um a@t M@um u@nster, Germany
C. Kriegeskotte, Universit@um a@t M@um u@nster, Germany
D. Lipinsky, Universit@um a@t M@um u@nster, Germany
Correspondent: Click to Email
ToF-SIMS and laser-SNMS are increasingly important tools for analyzing the elemental and molecular distribution in biological samples. However, in-vivo analyses of tissues or cell cultures are impossible because the sample must accommodate the vacuum conditions of the instrument. Thus, fixing the sample in its vital state, such as freezing, is essential. Sample preparation by cryofractioning or cryosectioning techniques followed by freeze-drying has been successfully used. However, these techniques exhibit several limitations. In order to overcome these limitations, a combination of a ToF-SIMS/laser-SNMS instrument and an in-vacuum cryosectioning instrument was developed for directly preparing and analyzing frozen non-dehydrated samples. In our presentation, we will discuss various sample preparation techniques for analyzing cell cultures and tissue samples and the possibility of obtaining 3D molecular images of frozen biological samples. Particularly, we will show that the analysis of frozen non-dehydrated samples with an in-vacuum preparation technique for exposing the interesting layers of the sample and creating pristine surfaces offers several advantages in comparison to techniques using freeze-dried samples. However, the analysis of cold samples may lead to problems with especially H@sub 2@O adsorption onto the cold surfaces. This is avoided by using a special temperature treatment. Our analysis showed that increasing the temperature to around -110 °C removes the adsorbed water from the top surface. At this temperature freeze-drying effects are not significant enough to influence the measurements during normal analysis times.