Electrospun polyvinyl alcohol (PVA) nanofiber fabrics functionalized by Cibacron Blue F3GA (CB) as an affinity ligand were prepared as efficient platforms for protein adsorption. Bovine serum albumin (BSA) was selected as a model protein to investigate their static adsorption behaviors. The protein adsorption capacities for the PVA nanofiber are 355.9 and 793.7 mg/g before and after CB modification, resulting in a 2.2 times increase. Then, dynamic experiments were conducted to determine the function of CB modification to the PVA nanofiber fabric. The effects of initial concentration and permeation rate on the dynamic adsorption behaviors for BSA of the CB-modified PVA nanofiber fabrics were also studied. The pseudo-first-order and pseudo-second-order kinetic models were used to analyze the kinetic adsorption data, and the latter was better fitted the experimental data. Furthermore, the adsorbed BSA can be easily eluted by a 0.1 M NaCl solution, and the CB-modified PVA nanofiber fabrics presented competent adsorption performance in the three-cycle reused experiment. Finally, the adsorption efficiency by the static and dynamic methods was compared. The obtained results demonstrate the potential of using the CB-modified PVA nanofiber for the affinity adsorption and isolation of proteins.
To improve the calculation accuracy of the contractile force in a shape memory alloy (SMA) knitted fabric actuator, which was developed in a previous study, we measured the Young's modulus, E, and wire diameter, d, of a SMA yarn in unheated (20 °C) and heated (100 °C) environments. Subsequently, the contractile force in the heated environment was calculated in terms of bending rigidity (EI) using the measured values of E and d. The accuracy of the theoretical contractile force, considering contraction and increment in EI, was improved when compared with that in the former one, which only considered contraction of the SMA yarn. Furthermore, to enhance calculation accuracy, we proposed a 2 dimensional stitch model for SMA plain knitted fabric. This model consisted of clothoid curves through four contact points, where each yarn crosses the other stitches and act forces. Further, this model could show the change in the curvature via the contraction of the yarn as well as the increase in its potential energy. Therefore, it was confirmed that this model is useful for calculating the contractile force of the SMA knitted fabric.