Evaluate the biocompatibility related to the material

This preview shows page 4 out of 5 pages.

evaluate the biocompatibility related to the material properties of each MEA according to international standards. We used end products manufactured by way of prototype fabrication processes rather than raw materials, and in vitro cytotoxicity assays were conducted using the extracts of MEAs following ISO 10993-5. 10 A variety of polymers have been tried as substrates for an MEA in a retinal prosthesis. We compared three types of polymer-based MEAs, including silicone-based platinum, poly- imide-based gold and liquid crystal polymer-based gold MEAs, of which the fabrication processes have been reported previously. 6–9 These polymers have been cited as suitable candidates for retinal prostheses. 9,12–20 However, each poly- mer has several disadvantages when considered to be used for such an implant. Silicone might be too brittle to make thin enough. Polyimide is known to absorb moisture and result in delamination of the metal at the electrode site or interface of polyimide layers. 21,22 Recently, LCP has been used as a new substrate material for retinal prosthesis MEAs, 9 having proper- ties of extremely low permeability of moisture and ions. 14,23 However, little is known about the efficacy and safety of LCP- encapsulated MEAs for retinal prostheses. In our study, in vitro cytotoxicity assays were done based on indirect evaluation using the extracts of each specimen, including the evaluations by phase contrast microscopy and MTT assays. Under microscopic examinations, all types of polymer-based MEAs showed no significant morphologic changes or growth reduction of fibroblasts compared with control groups irrespective of diluted ratios of extracts. The MTT assay is considered a good quantitative method to
Image of page 4

You've reached the end of your free preview.

Want to read all 5 pages?

  • Spring '14
  • Cytotoxicity, cell viability, MTT assay, retinal prosthesis, polymer-based MEAs

{[ snackBarMessage ]}

What students are saying

  • Left Quote Icon

    As a current student on this bumpy collegiate pathway, I stumbled upon Course Hero, where I can find study resources for nearly all my courses, get online help from tutors 24/7, and even share my old projects, papers, and lecture notes with other students.

    Student Picture

    Kiran Temple University Fox School of Business ‘17, Course Hero Intern

  • Left Quote Icon

    I cannot even describe how much Course Hero helped me this summer. It’s truly become something I can always rely on and help me. In the end, I was not only able to survive summer classes, but I was able to thrive thanks to Course Hero.

    Student Picture

    Dana University of Pennsylvania ‘17, Course Hero Intern

  • Left Quote Icon

    The ability to access any university’s resources through Course Hero proved invaluable in my case. I was behind on Tulane coursework and actually used UCLA’s materials to help me move forward and get everything together on time.

    Student Picture

    Jill Tulane University ‘16, Course Hero Intern