Week 8
May 26, 2017
This week we took the first steps into acquiring research data. We visited Dr. Cheng's lab and created sufficiently mixed solutions of alginate using a centrifuge and a magnetic stirrer/hot plate. This is a significant improvement over the poor, hand-mixed solutions that we made in the Innovation Studio. Also, in addition to using red food coloring as our substitute for medication, we added a protein called fluorescin-isothiocynate (FITC-BSA). There was .5 mg of protein in 7 mL of alginate solution.
Once again, we used a syringe to inject the alginate solution into a bath of calcium chloride. The first time was unsuccessful because we injected the alginate while the syringe needle was above the calcium chloride; We discovered that we had to inject the alginate while the needle was inside the calcium chloride to allow crosslinking to occur. The second times yielded better results. We made two long strings: one would be covered in chitosan while one did not. After this procedure, we let the fibers sit in saline water for several minutes before dipping one of the strings in chitosan. Finally, we transferred both strings into a test tube filled with water.
A closer look at the chitosan- A closer look at the plain
coated alginate fiber alginate
This week we took the first steps into acquiring research data. We visited Dr. Cheng's lab and created sufficiently mixed solutions of alginate using a centrifuge and a magnetic stirrer/hot plate. This is a significant improvement over the poor, hand-mixed solutions that we made in the Innovation Studio. Also, in addition to using red food coloring as our substitute for medication, we added a protein called fluorescin-isothiocynate (FITC-BSA). There was .5 mg of protein in 7 mL of alginate solution.
Once again, we used a syringe to inject the alginate solution into a bath of calcium chloride. The first time was unsuccessful because we injected the alginate while the syringe needle was above the calcium chloride; We discovered that we had to inject the alginate while the needle was inside the calcium chloride to allow crosslinking to occur. The second times yielded better results. We made two long strings: one would be covered in chitosan while one did not. After this procedure, we let the fibers sit in saline water for several minutes before dipping one of the strings in chitosan. Finally, we transferred both strings into a test tube filled with water.
Test tubes containing alginate dipped in
chitosan (right) and not dipped in chitosan (left)
coated alginate fiber alginate
Based on qualitative observations, we saw that the alginate dipped in chitosan retained its color, while the one not dipped in chitosan had quickly turned transparent. This indicates that the chitosan-coated fiber had a slower release rate of its contents than the one that was not coated. We handed the two samples over to one of Dr. Cheng's lab assistants in order to measure their absorbences through spectroscopy at different times, specifically after 15 minutes, 1 hour, 2 hours, 4 hours, and 8 hours.
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