| AVS 61st International Symposium & Exhibition | |
| Helium Ion Microscopy Focus Topic | Thursday Sessions |
| Session HI+2D+AS+BI+MC-ThM |
| Session: | Fundamental Aspects and Imaging with the Ion Microscope |
| Presenter: | Torgny Gustafsson, Rutgers University |
| Authors: | S. Shubeita, Rutgers University L. Muller, NIDA-IRP H.D. Lee, Rutgers University C. Xu, Rutgers University D. Barbacci, Ionwerks Inc. K. Baldwin, NIDA-IRP J.A. Schultz, Ionwerks Inc. L. Wielunski, Rutgers University T. Gustafsson, Rutgers University L.C. Feldman, Rutgers University A.S. Woods, NIDA-IRP |
| Correspondent: | Click to Email |
MILDI mass spectrometry is an emerging tool for detecting changes in brain tissue. An ~20 nm thick region of rat brain tissue implanted with 1013/cm2 Au(400)4+ nanoparticle (NP) ions at 40 keV, produces analytically useful signals of lipids, peptides and proteins using a pulsed nitrogen laser [1]. When a dose of 1012/cm2 500 eV AgNP (approximately 6 nm diameter) is implanted as a matrix, only lipids are detected [2]. To understand this it is essential to measure the spatial distribution of the nanoparticles. We have used Rutherford Backscattering and Helium Ion Microscopy imaging to determine the Ag NP distributions and areal densities in an implanted coronal rat brain section. We then correlate the ion beam analysis and imaging with individual lipid intensities from several hundred MILDI mass distributions. The results show a high degree of uniformity of the Ag atomic and particulate distribution on a sub-micron scale among different regions of the tissue. Helium Ion Microscopy provides verification of NP matrix uniformity, validating the use of MILDI for quantitative mass analysis.
This work is partially supported by NSF (DMR 1126468), NIH (R44DA030853-03) and IAMDN.
[1] A. Novikov et al, Analytical Chemistry 76 (2004) 7288. [2] S. N. Jackson et al, Analyt. and Bioanal. Chem. (e-pubed Dec 2013).