The controlled

and well-aligned CNFs are used to investigate cell spreading phenomena and related issues of cellular biocompatibility. The fundamental issues of cell spreading and extension guiding in a preferential direction are experimentally performed on parallel-aligned and grid patterns for the purpose of better realization of the ability to manipulate cellular architecture. Methods Materials Chitosan from crab shells with 85% deacetylation (Mw = 50 to 190 kDa) was purchased from Sigma Chemical Co (St. Louis, MO, USA). PEO (Mw = 900 kDa; Triton X-100™) was provided by Acros Co. (Geel, Belgium), and dimethylsulfoxide (DMSO) was obtained from Tedia Co. (Fairfield, OH, USA). All reagents were used as received from the manufacturer without further purification. Preparation of stock solutions for electrospinning Chitosan solution (5%) and 1% PEO solution were first selleck prepared separately by dissolving chitosan in 0.5 M acetic acid, then vacuumed in an oven at 0.8 Torr to remove air bubbles [17]. Solutions containing 0.5 wt.% of

Triton X-100™ and 5 to 10 wt.% of DMSO were mixed with the chitosan/PEO solutions, and the mixtures were again stirred for 16 h and vacuumed to remove air bubbles before use. Polypyrrole substrates Soluble PPy was synthesized chemically using ammonium persulfate (APS) as an oxidant and a dopant. Pyrrole of 0.3 mol and 1:50 ratio see more of APS and pyrrole solution were mixed with 500 ml of distilled water. The solution was spin-cast on a polystyrene Petri

dish to obtain a PPy film [25], and the electrical conductivity was measured to be 7.25 kΩ/square using the four-point probe method. NFES setup The stock solution for electrospinning was fed into a 1-ml disposable syringe fitted with a 0.4-mm-wide needle tip, the applied electrostatic voltage was in the range of 800 to 1,000 V (AU-1592, Matsusada Precision Inc., Kusatsu, Japan), and the distance between the syringe tip and the grounded collector was 500 μm. The substrate was mounted onto a programmable XY stage (Yokogawa Inc., Tokyo, Japan), controlled by a personal computer, which allows movement of the sample during nanofiber deposition. The experiment was carried out at room temperature and atmospheric Phosphatidylinositol diacylglycerol-lyase pressure. Cell culture, adhesion, and spreading Human embryonic kidney cells (HEK 293T) were cultured in 25-cm2 flasks in Dulbecco’s modified Eagle medium containing 10% fetal bovine serum. The cell suspension was added to each nanofiber pattern in a PPy-modified polystyrene Petri dish and cultured in an incubator at 37°C with 5% CO2. In order to seed HEK 293T cells onto the CNF, a confluent monolayer of cells was trypsinized and centrifuged at 1,000 rpm for 4 min. After supernatant Smoothened Agonist supplier removal and re-suspension in fresh culture medium, cells were transferred to a PPy-modified polystyrene Petri dish.