Biodegradable polymers have potential as a scaffold material for making small diameter artery bypass grafts. To resist thrombosis, maintain biocompatibility and enhance the remodeling of the grafts, it is crucial to modify polymer scaffolds so that the grafts have antithrombogenic capacity and allow cell infiltration. In this study, two methods of aminolysis on electrospun poly-L-lactide-co-caprolactone (PLCL) microfiber vascular grafts are compared: plasma treatment method and Fmoc-PEG-diamine insertion method. Both methods successfully inserted amino groups on the polymer graft for heparin conjugation. However, plasma treatment resulted in significantly higher initial heparin density and higher heparin stability on PLCL microfibers than Fmoc-PEG-diamine treatment. In addition, mechanical testing demonstrated that the plasma treatment method maintained PLCL microfiber tensile strength after heparin conjugation. Fmoc-PEG-diamine insertion method compromised the mechanical property due to partial fiber melting and structure disruption. Subcutaneous implantation of the grafts in a rat model showed that heparin coating with both methods promoted cell infiltration. This study provides a rationale to optimize the biomolecule conjugation on electrospun PLCL scaffolds, and will have applications in tissue engineering vascular grafts and other tissues.

No abstract

Plasma surface conditioning is now a commonly accepted practice in many applications. Three types of plasma systems are commonly commercially used: low pressure (LP), atmospheric plasma (AP) and corona (CP). This paper compares the attributes of each of these available types. We suggest there are many applications well suited to the use of atmospheric plasma jet in electronic manufacturing. This paper provides examples of the benefits of using atmospheric plasma for applications including: improving adhesion by plasma surface modification, reduction of metal oxide surfaces and deposition of protective barrier layers for LEDs. These examples demonstrate the unique potential of atmospheric plasma jets to provide advantages in applications important in electronic assembly and manufacturing including initial characterization data, references to final applications and next steps.

Biological systems respond to and interact with surfaces. Gas plasma provides a scalable surface treatment method for designing interactive surfaces. There are many commercial examples of plasma-modified products. These include well plates, filtration membranes, dispensing tools, and medical devices. This chapter presents an overview of gas plasma technology and provides a guide to using gas plasma for modifying surfaces for research or product development.

No abstract