Week 5 Analyzing SEM Images

In week 4, the group began to research bacteria that could exist in water supplies and that would cause harm to the human body. Also in Week 4, the nanofibers were spun samples of PEO using different variable lengths that were stated was one of the parameters that would be altering. The spun PEO samples were at lengths 4, 6, 8, 10, 12, and 16 cm. These lengths are the distances between the syringe and the collecting plate . Altering these lengths changed the different diameters of the Electrospun fibers. The goal is to create a filter using these fibers and below is an analysis of the diameters of the fibers:

PEO - 4cm



Figure 11. PEO Spun 4cm

Figure 11 illustrates the diameters of the spun fibers at a distance of 4 cm from the needle and the collecting plate. This image is zoomed so that it would be easy to calculate the distance. Using ImageJ the group was able to estimate the distances of the threads. To take a proper estimate, the measurements were taken from 30 different threads. the average of the diameters were 67.17 nm. the standard deviation was 0.0175 μm.

PEO - 6cm

Figure 12. Spun PEO 6cm

In Figure 12 you see one nano fiber that was woven together through the electrospinning process. Using the Image J measuring tool that was used gave the results that the the fiber has diameter of 10 μm. This holds true to the research that was conducted earlier in the experiment. The diameters should increase to a certain point until they will decrease again. This comparison between 4 cm shows that the results are correct in creating new filtration technology. The measurements were taken from 30 fibers that are comming off of the long big fiber. the measurement average was. 161.49 nm. the standard deviation is 0.0801 μm.

PEO - 8cm

Figure 13. Spun PEO 8 cm

The SEM image at 8 cm also resulted in a picture of only one thread. The diameter in this thread was 7.485 μm which is a little bit finer than the thread spun at 6 cm. Although it is thinner than the thread from 6cm, the 8cm PEO thread is still thicker than the diameter of the thread spun at 4cm which was 0.5722 μm. As in the image before there was only one thread so there was no average taken and the final diameter at 8cm is 7.485 μm. 

PEO - 10cm



Figure 14. Spun PEO 10cm



 In Figure 14 the measurements were taken from 30 different fibers in the SEM image. This was just to get a better approximation of the diameters because there were more fibers spun in the 10cm sample than there was in the 4cm sample. The average of the diameters was 81.6 nm. The standard deviation 0.025 μm.

PEO - 12cm



Figure 15. Spun PEO 12 cm



The PEO results at 12 cm is the best just because of the quantity of the fibers that were spun and collected. Also the diameter is the smallest of all the fibers that were spun before. This image had lots of fibers and it was zoomed to 200nm. the average of 30 fibers is 49.52 nm. the standard deviation of the fiber diameters 14.39 nm

PEO - 16cm



Figure 16. Spun PEO 16cm 



In Figure 16 you see that the fibers don't seem to be spun as well as the fibers before. The diameters are sill very small for the fibers but the fibers do not appear to be as stable. This sample was very running and did not have good results. The fiber diameters 120.56 nm and the standard deviation is 0.036 μm.

The ideal fiber seems to be the fiber spun at the distance of 12 cm. These fibers gave the smallest diameter which is what is needed when spinning fibers for a filter. With these current results it shows that the fiber chosen to spin would be a filter using a 12 cm distance, but there will  also testing the angle of spin to get the ideal distance and angle for a fiber. When the angle results were acquired will be spinning an ideal filter out of the fibers. Currently the only realization is that one ideal variable which is 12 cm.