Take a sneak peek at the new NIST.gov and let us know what you think!
(Please note: some content may not be complete on the beta site.).
NIST Authors in Bold
|Author(s):||Christine M. Mahoney; S V. Roberson; John G. Gillen;|
|Title:||Dynamic SIMS Utilizing SF5+ Polyatomic Primary Ion Beams for Drug Delivery Applications|
|Published:||June 01, 2004|
|Abstract:||The behavior of various biodegradable polymer films (e.g. polylactic acid, polyglycolic acid and polycaprolactone) as well as some model drugs (theophylline and 4-acetamidophenol) under dynamic SF5+ primary ion bombardment is explored. A series of polylactic acid films containing varying concentrations of 4-acetamidophenol are also analyzed under similar conditions. The resultant molecular depth profiles obtained from these polymer films doped with drug show very little degradation in molecular signal as a function of SF5+ primary ion dose, and it was found that the molecular ion signals of both polymer and drug remained constant for ion doses up to ~5x1015 ions/cm2. In addition, the polymer film / Si interface was well defined which may imply that sputter-induced topography formation was not a significant limitation. These results suggest that the structure of the biodegradable polymers studied here which all have the common structural unit, R-CO-O-R, allows for a greater ability to depth profile due to ease of bond cleavage. Most importantly however, these results indicate that in these particular polymer systems, the distribution of the drug as a function of depth can be monitored.|
|Citation:||Applied Surface Science|
|Keywords:||cluster,depth profile,drug delivery,SF5+,TOF-SIMS|
|Research Areas:||Nanotechnology, Chemistry|