Drug Loading and Release. We evaluated the drug-loading and release properties of the prepared NWFs to confirm their ability as drug delivery systems. Diclofenac sodium was selected as the model drug. The drug-loaded PP NWFs were prepared by immersion in a diclofenac aqueous solution and washing with distilled water. The amount of drug loaded on Ox-80-CD was calculated to be 3.67±0.22 μmol/g based on the change in the UV absorbance of the diclofenac solution (276 nm) before and after immersion. Subsequently, the drug release behavior in the phosphate buffer (pH 7.4) was studied using a time course with a UV-visible spectrophotometer. As shown in Figure , 60% of the loaded drug was released within 1 h for Ox-80-CD, after which slow release of the remaining drug was observed for the next 12 h. This result contrasts with the case of plasma-CD, in which all the loaded drugs were released upon immersion. This suggests that our method is superior for preparing drug-loaded PP NWFs. In addition, the reusable property as a drug carrier was evaluated. As shown in Figure , sustained drug release behavior was also observed in second run. Herein, we defined the values of Δ1 (0 to 10 min) and Δ2 (10 min to 48 h) as the drug release amount during a given time period (Table ). The value of Δ1 implies an initial burst release of the drug, which may be caused by the drug loosely absorbed in the surface. In contrast, Δ2 represents the amount of slow-release drug, and it should be noted that these amounts are comparable in the first and second use. This result implies that Ox-80-CD shows excellent slow drug release property in repeated use.