Time-of-Flight Secondary Ion Mass Spectrometry (TOF-SIMS) for High-Throughput Characterization of Biosurfaces
S V. Roberson, A Sehgal, Albert J. Fahey, Alamgir Karim
In this approach, a coated polymer film was exposed to UV-ozone treatment through a variable density filter, producing a surface energy gradient with a systematic variation of the surface chemistry across the substrate. These UV-ozone exposed films were chemically analyzed by TOF-SIMS and were exposed to cells for biocompatibility evaluation. We used the TOF-SIMS IV (with automated acquisition and analysis) to correlate the surface free energy changes (assessed via contact angle measurements) with the chemical species present on the surface of the UV-ozone-exposed film. In this preliminary work, we tracked the secondary ion intensities of various species along the 45 mm length of the polymer film. We noticed consistent trends, with the secondary ion signals for oxidized species steadily increasing with the increasing hydrophilic nature of the surface (information obtained from contact angle measurements). We also correlated the degree of cell adhesion (as measured using staining techniques) and the specific (physico-chemical) polymer surface modifications produced by the UV-ozone exposure. This approach may be further extended to probe the mediating absorbed serum protein distribution that constitutes the bio-interface in cellular reception of polymeric materials.
Applied Surface Science
polymers, SIMS, UV-ozone
, Sehgal, A.
, Fahey, A.
and Karim, A.
Time-of-Flight Secondary Ion Mass Spectrometry (TOF-SIMS) for High-Throughput Characterization of Biosurfaces, Applied Surface Science
(Accessed May 27, 2023)