Paper AS-TuA9
3D Molecular Characterization of a Drug Delivery System

Tuesday, October 16, 2007, 4:20 pm, Room 610

Coronary implants that incorporate a drug delivery system are being developed at an increasing rate. It is important for a variety of reasons to characterize such in vivo drug delivery devices and to relate the chemical and physical properties to how the system will function. This study focuses on the characterization of a drug eluting stent coating that consists of rapamycin in a poly(lactic-co-glycolic acid) (PLGA) matrix. The goal is to understand the lateral and depth distribution of the drug in the polymer matrix. Additionally, the drug distribution is studied as a function of elution time. Information regarding the lateral and depth distribution of rapamycin in PLGA, and the distribution as a function of elution time, was determined by TOF-SIMS depth profiling with a C₆₀ cluster ion source. Where appropriate, the TOF-SIMS results will be compared to the results obtained by XPS and confocal Raman. The experimentally-determined 3D chemical structure as a function of elution time, in conjunction with the elution profiles, may be used to enhance the design of future in vivo drug delivery systems.