Cardiomyocytes, the beating cells of the heart, are highly dependent on oxygen for survival and function. Early work in cardiac muscle tissue engineering revealed that cardiomyocytes only survived within 150 microns of the scaffold's edge due to limitations in oxygen diffusion. Sphere-templated poly(ethylene glycol) (PEG) hydrogel scaffolds were developed to provide paths for the passive diffusion of oxygen and other nutrients, which is expected to enhance survival of the engineered tissue. Scanning electrochemical microscopy (SECM) provides spatially-resolved information about chemical species concentration. Electrochemical measurements reveal that diffusion within the crosslinked structure of the non-porous bulk hydrogel regions can be tuned by varying the gel crosslinking density (e.g. by changing PEG molecular weight and/or weight percent in the hydrogel). Preliminary studies also indicate that pore topography/size as captured by in-situ electrochemical images is consistent with SEM images of dried hydrogels. SECM measurements allow us to quantify the contribution of the microscopic and nanoscopic pores to providing oxygen and other nutrients to the scaffold interior.
Conference Dates: October 7-12, 2007
Conference Location: Washington, DC, DC
Conference Title: Fall Mtg. of the Electrochemical Society
Pub Type: Conferences
diffusion, hydrogel scaffolds, scanning electrochemical microscopy