Janet L. deGrazia

Mucoadhesion of poly(2-hydroxyethyl methacrylate) is improved when linear poly(ethylene oxide) chains are added to the polymer network

Abstract The mucoadhesive capacity of poly(2-hydroxyethyl methacrylate) (PHEMA) microspheres was studied in contact with Sprague-Dawley rat jejunum atpH = 6 and at 22°C. Dry PHEMA microparticles exhibited adequate mucoadhesive capacity, which was independent of nominal crosslinking ratio. When PHEMA microparticles were loaded with linear PEO chains of molecular weight 1000, the mucoadhesive capacity increased significantly, almost doubling. This behavior was attributed to a significant increase of the PEO chains penetrating across the mucosal tissue. However, very long pendant chains could have a detrimental effect on interpenetration, as was shown with PHEMA microparticles loaded with PEO chains of molecular weight 100 000 which exhibited only a limited mucoadhesive capacity. This was the result of extensive entanglements by the long PEO chains and impediment of chain mobility across the PHEMA/mucosal interface.

Beyond the pipeline: building a K-12 engineering outreach program

Outreach to the K-12 community by engineering faculty and students is not a novel idea. There have long been those individuals passionate about sharing the fun and excitement of solving problems, designing and building new devices, and creating what has never existed before. What is new is an increased national awareness of the importance of nurturing connections between the demands of the technological workplace, institutions of higher education, and the K-12 community of teachers and learners. This paper provides guidance on planning and implementing a K-12 engineering outreach program using the outreach component of the Integrated Teaching and Learning (ITL) Program at the College of Engineering and Applied Science, University of Colorado at Boulder (USA), as a case study.