AVS 51st International Symposium
    Applied Surface Science Monday Sessions
       Session AS-MoA

Paper AS-MoA6
Applications of Cluster SIMS for Molecular Depth Profiling in Biomaterial Systems

Monday, November 15, 2004, 3:40 pm, Room 210A

Session: SIMS II - Biological and Organic
Presenter: C.M. Mahoney, National Institute of Standards and Technology
Authors: C.M. Mahoney, National Institute of Standards and Technology
J.-X. Yu, State University of New York at Buffalo
J.A. Gardella, Jr., State University of New York at Buffalo
A.M. Johnson, Massachusetts Institute of Technology
R. Langer, Massachusetts Institute of Technology
Correspondent: Click to Email
Polymeric biomaterials have numerous clinical applications including as surgical implants, absorbable sutures, tissue engineering scaffolds and drug delivery devices. Time-of-Flight Secondary Ion Mass Spectrometry (TOF-SIMS) has proven to be particularly useful in the surface analysis of these polymeric biomaterials@super 1@. However, much of this work has been done with monoatomic primary ion beams, which have a large amount of beam-induced damage associated with them. This precludes the ability to obtain in-depth information from organic samples. Compared to monoatomic ion bombardment, cluster primary ion beams, such as SF@sub 5@@super +@ have resulted in decreased subsurface damage and increased sputter rates in some cases, allowing the ability to depth profile in organic and polymeric materials for the first time@super 2-3@. This talk will briefly describe the ongoing research efforts at NIST to further develop cluster SIMS as a tool for biomaterials characterization. We have already shown the ability to depth profile in model polylactic acid (PLA) based drug delivery systems using cluster SIMS@super 3@. More recently, we have been able to successfully measure the extent of preferential segregation in polylactic acid / polyethylene glycol (PLA/PEG) blends as well as determine the in-depth distribution of acetamidophenol doped PLA films as a function of increasing degradation time. We have also successfully obtained information as a function of depth in a novel drug delivery microchip. This work further demonstrates the increasing utility of cluster SIMS for biomaterials applications. @FootnoteText@ @footnote 1@ Lee, J.-W.; Gardella, J.A. Jr. Analytical Chemistry 75 (2003) 2950-2958.@footnote 2@ Gillen, G.; Roberson, S.; Rapid Commun. Mass Spectrom. 12 (1998) 1303.@footnote 3@ Mahoney, C.M.; Roberson, S.V.; Gillen, J.G. in "Depth Profiling of 4-Acetamidophenol Doped Poly(lactic Acid) Films Using Cluster SIMS"; Analytical Chemistry, Accepted March 2004.