Feasibility of fluoroelastomer-246B as the substitute of bile duct

Kai LIU; Guangyi WANG; Songyang LIU

ABSTRACT

BACKGROUND:

Fluoroelastomer-246B has better histocompatibility than polyethylene and polypropylene, which is the same as expanded polytetrafiuoroethylene (ePTFE). Besides, fluoroelastomer-246B has better rigidity than ePTFE, so it is hard to deform.

OBJECTIVE:

To investigate the feasibility of fluoroelastomer-246B as a human implant in vivo and a substitute of human bile duct by the test of bile soak, routine sterilized method, and implantation into rat abdominal cavity.

DESIGN:

A controlled observation.

SETTING:

First Hospital of Jilin University & Key Laboratory of Education Ministry for Supramolecular Structure and Material of Jilin University.MATERIALS This study was performed at the Key Laboratory of Education Ministry for Supramolecular Structure and Material of Jilin University from June 2006 to March 2007. A total of 35 male Wistar rats of clean grade, aged 4-5 weeks,weighing 140-160 g, were provided by Laboratory Animal Center, School of Basic Medical Sciences, Jilin University [Permission No. SCXK (Ji) 2003-0001]. Prior to surgery, the Wistar rats were fasted for 5 hours, but they were allowed to access to water freely. The main materials used in the present study were as follows fluoroelastomer-246B (Yangzhong Municipal Rubber & Plastics Plant, China), ePTFE(Shanghai Suo-Kang Medical Implants Co.,Ltd., China).

METHODS:

Rectangular fluoroelastomer-246B thin slices (50 mm×10 mm×0.5 mm) made were placed in a beaker filled with fresh bile, and preserved in a 37 ℃ thermostat container. The tensile strength, thermal decomposition temperature and glass transition temperature of fluoroelastomer-246B were tested after 30 days, and the results were compared to those before soaking to investigate whether the physical-chemical properties of fluoroelastomer-246B slices would change after soaking in the bile environment for a long time. The rectangular fluoroelastomer-246B thin slices made as above were sterilized by boiling method, formaldehyde vapors fumigating method, and formaldehyde fluid soaking method. The indices mentioned above were measured, and the data were compared to those before sterilizing to identify whether fluoroelastomer-246B could be used after sterilizing. The same-size slice of fluoroelastomer-246B,ePTFE, polypropylene and polyethylene was separately implanted into rat abdominal cavity. The slices were taken out after 30 days, and the pathological sections of surrounding tissues were made to observe whether allergic response and/or inflammatory reactions existed.MAIN OUTCOME

MEASURES:

After fluoroelastomer-246B thin slices were soaked in bile for 30 days, their tensile strength, thermal decomposition temperature and glass transition temperature were tested, and the results were compared to those before soaking. After fluoroelastomer-246B thin slices were sterilized by boiling method, formaldehyde vapors fumigating method, and formaldehyde fluid soaking method, the indices mentioned above were measured, and the data were compared to those before sterilizing. The numbers of cells with allergic response and cells with inflammatory reaction were counted.

RESULTS:

After soaking in the fresh bile for 30 days, the tensile strength, thermal decomposition temperature and glass transition temperature of fluoroelastomer-246B changed slightly compared to before soaking (P＞0.05).Fluoroelastomer-246B could well antagonize mechanical stress after bile soaking and sterilizing. Under going sterilizing by boiling method, formaldehyde vapors fumigating method and formaldehyde fluid soaking method separately, the tensile strength, thermal decomposition temperature and glass transition temperature of fluoroelastomer-246B had no marked changes (P＞0.05). No noticeable allergic response was observed after fluoroelastomer-246B was implanted into rat abdominal cavity, whereas slight inflammatory reaction was detected, which was similar to ePTFE (P＞0.05).

CONCLUSION:

The primary physical-chemical properties of fluoroelastomer-246B do not change after soaking in bile for 30 days. Fluoroelastomer-246B can well antagonize mechanical stress and be used after sterilizing without metaphysis or allergic response. Therefore, fluoroelastomer-246B can be used as a substitute of bile duct.