| Summary: | 碩士 === 逢甲大學 === 紡織工程所 === 98 === In this study, there are two part of research, one is electrospun Poly(vinyl alcohol) nano-fiber, the other one is combined the advantage of electrospun and electrochemical biosensor in order to produce a high-sensitive glucose biosensor. The first part of this study used PVA polymer as research material, In this part, we study the variations of Taylor Cone, the stable jet length and the fiber configuration by changing the electrospun parameters in order to find the best electrospun parameter of PVA. We also used a self-assembled electrospun device to design a special mechanism, which was capable of changing electrostatic field direction, to study the effect of directional change in the electrostatic field on electrospun behaviors. The second part we combined the advantage of electrospun and electrochemical biosensor in order to produce a high-sensitive glucose biosensor, and comparison of nano-fiber membrane the differences between PVA dipping film. In addition, this study also found the electrospun parameters, enzyme immobilization method, PVA cross-linking parameters of the sensitivity effects to glucose biosensor.
The first part of the experimental results, type of jet motion is whip in low-voltage and medium-voltage; the type of jet movement is split in high-voltage because the system is instable. Viscosity of PVA fiber configuration influence the key factors, the 7%wt PVA(383cp) is the best viscosity to electrospun PVA polymer, the fiber configuration become bead fiber while the viscosity was less than 383cp, it will increase fiber diameter while configuration was higher than 383cp. Experimental results showed the rising of the viscosity of the solution increased the length of jet, and it reduced the need of the electric field strength that made Taylor Cone stable. The efficiency of spinning was highest when the Taylor Cone was in a stable range and the length of jet reached maximum, and we can get uniform and the thinnest diameter of fiber. About effect of electrostatic field directions on electrospun behaviors, the data showed some similarities between the mechanisms of the two systems. As voltage increased, the number of loops increased in both systems. This is the primary mechanism for obtaining thinner fibers. When the Taylor cone shrank, the variance increased; therefore, the mechanism driving the configuration of thinner fiber stopped. The collector charging system displayed shorter straight jet length, larger splaying angle, larger charge density, and better fiber forming mechanisms, resulting in smaller fiber diameter with a lower variance. In addition, this study confirmed that an increase in humidity resulted in an increase of beads. The tests indicated that a unique mechanism present in the collector charging system was able to suppress the increase of beads. Finally, we prepared 209nm PVA nanofibers by collector charging system.
In the second result, the glucose biosensor prepared by electrospinning was better than the other process method, and the sensitivity was 1.9 times more than PVA-film. The immobilization temperature played an important role in immobilization process. The best immobilization temperature was 50℃, and its sensitivity was 2.4 times more than the sensitivity of PVA-ilm. The method of immobilization has a great influence on GOx/PVA composite electrospinning membranes. For the glucose biosensor prepared by electrospinning, the cross-link with glutaraldehyde steam was better than heat treatment, and the best cross-linking time was 15 mins. The addition of gold nanoparticles could increase the sensitivity of GOx/PVA glucose biosensor. When the addition was 5%, the sensitivity was the highest (37.65μA/mM) and 28.5 times more than PVA-film. Combining the best parameter of electrospinng technology and cross-linking method could produce a high-sensitive glucose biosensor.
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