FY 2000 Materials And Device Characterization
- Experimental Pathology: Cardiovascular Devices
- Tissue Engineered Medical Products Standards (TEMPS)
- Powder Measurement on Medical Glove through the Participation in ASTM Working Group
The focus of this program is to develop and assess suitable characterization methods and the generation of baseline data of the chemical, physical, and mechanical properties of medical devices and their materials. The effects of devices, drugs, radiation, etc. on the physical properties of tissue, as well as research into the determination of specific exposure limits are included in this area of study. By undertaking work in this program area, OST will help CDRH with its regulatory mission by participating in the development of consensus standards and characterization techniques that allow for the timely review of many diverse products, including absorbable sutures and vascular grafts. With OST’s extensive expertise in materials, the Office drafted standards that assist manufacturers in assessing the MRI compatibility of their devices by evaluating the potential for soft tissue damage by either torque or unbalanced linear forces in the presence of large magnetic fields. The work described below on the development of a standard methodology for the measurement of powder on gloves aided in the drafting of regulations concerning the allowable limits of powders on gloves.
Experimental Pathology: Cardiovascular Devices
Key words: pathology, valves, grafts
The objective of the experimental pathology program is to identify potential failure modes associated with the use of implantable cardiovascular devices as well as the elucidation of pathologic mechanisms responsible for their failure. Studies of explanted replacement heart valves, vascular grafts and angioplasty-injured coronary arteries are ongoing. Studies completed this year include 1) the development of experimental pathology methods for the evaluation of tissue engineered replacement heart valves and small diameter vascular grafts; 2) a morphologic study of decellularized carotid artery vascular grafts; and 3) the evaluation of a swine model to assess the preclinical safety of mechanical heart valves.
Tissue Engineered Medical Products Standards (TEMPS)
Key words: standards, tissue engineering
Division IV of ASTM F04 has established itself as the recognized leader, both nationally and internationally, in the development of TEMP standards. International liaisons have been established with other standards organizations that have expanded international involvement with the consensus process.
An important initiative is an ASTM International Symposium for Tissue Engineered Medical Products Standards to be held in Miami Beach, Florida, November 4-5, 2002, in conjunction with Committee Week and proposed as a "back-to-back" meeting with the Tissue Engineering Society International biannual meeting. The goals for the symposium are to review the technology, the use of standards, and the need for standards.
Powder Measurement on Medical Glove through the Participation in ASTM Working Group
Key words: powder measurement, powdered glove, powder-free glove
Prior to the present work, ASTM D 6124 – 97 was the standard test method for residual powder on medical gloves described as powder-less, powder-free or no powder. Due to the proposed powder limit on "powdered" gloves by FDA, there was a need to modify how larger amounts of powder were measured. The Division of Mechanics and Materials Science laboratory in OST participated in the ASTM D 11.40 round robin method development. By changing to a larger filter paper size, using the multiple fresh water washes per glove, minimizing extractions/filter, preconditioning of the filter, and agitating during the wash, a new Standard Test Method D 6124 - 00 was established. This method can be used for quantitation of powder on both powdered and powder-free gloves.