No abstract

No abstract

The surfaces of the polystyreneˆlms spin-coated on glass were modiˆed by carbon negative-ion implantation with various ion doses from 1×10 14 to 3×10 16 ions/cm 2 at 5 and 10 keV. The implantation conditions with and without a pattering mask were for investigation of the cell-attachment properties and for evaluation of surface physical properties of contact angle, respectively. The contact angles of modiˆed surface were investigated by pure water drop and air bubble method. The lowest angle value of the implantedˆlms at 5 and 10 keV were approximately 72°at 3×10 15 ions/cm 2 after dipping in the de-ionized water for 2 hours. The lowering of contact angles on C-implanted surfaces when increase the ion dose is due to formation of the OH and CO bonds. Nerve-cell-attachment properties of modiˆed surface were investigated by the nerve-like cell of rat adrenal pheochromocytoma (PC12h) in vitro. After 2 days culture of the PC12h cells, no cells attached on the polystyrenê lms implanted with low ion dose from 1×10 14 to 3×10 14 ions/cm 2. On the polystyreneˆlms implanted with the dose order of 10 15 ions/cm 2 , the cells selectively attached only on the implanted region. Whereas on the surfaces implanted with high dose such as 1×10 16 and 3×10 16 ions/cm 2 mostly cells attached on the implanted region, and some attached on the unimplanted region, as well as cells were abnormal in shape and large size. Therefore, the suitable dose implantation for the selective-attachment of nerve-cells on the polystyreneˆlms implanted at 5 and 10 keV were obtained around the dose order of 10 15 ions/cm 2 , and the best condition for the selective attachment properties was at 3×10 15 ions/cm 2 corresponding to the lowest contact angle.