Bio-packaged transponder MEMS implanted in rats.
A novel hydroxyapatite-based hybrid material with controlled porosity was designed as a bio-package to implant micro-electro-mechanical systems (MEMS) in living organisms. The biomaterial was prepared using synthetic stoichiometric hydroxyapatite powder reacted with a chemical-active, solvent-free, alkyd-based polyurethane. This porous material has interconnected pores with sizes between 100 and 350 μm and a pore volume fraction of 50%, fulfilling the requirements for implants. The biomaterial additionally has high wearing resistance and hydrolytic stability providing high endurance properties. The bio-package was characterized mechanically and morphologically using X-ray diffraction, scanning electron microscopy, densitometry, abrasion and mechanical tests. Twelve packaged micro-electro-mechanical systems were implanted subcutaneously into rats and tested for up to 9 months with good acceptance as revealed by the histological analysis performed on the soft tissue surrounding each implant.
Centro de Física Aplicada y Tecnología Avanzada, Universidad Nacional Autónoma de México, Juriquilla, Querétaro, México. rogelior@unam.mx
R
R
Rodriguez
A M
AM
Loske
M
M
Estevez
S
S
Vargas
R
R
Salazar
F
F
Pacheco
J
J
Vazquez-Carpizo
J M
JM
Gamboa
D000818:Animals; D001672:Biocompatible Materials / Q000737:chemistry*; D017886:Durapatite / Q000737:chemistry*; D055119:Elastic Modulus; D005260:Female; D055617:Micro-Electrical-Mechanical Systems; D011140:Polyurethanes / Q000737:chemistry; D016062:Porosity; D019736:Prostheses and Implants; D051381:Rats; D017208:Rats, Wistar; D017550:Spectroscopy, Fourier Transform Infrared; D014961:X-Ray Diffraction
D001672:Biocompatible Materials; D011140:Polyurethanes; D017886:Durapatite