This week, we edited the entirety of the blog to provide additional information and clarity. We continued working on the final presentation and the test results/discussion section of the final report. We might redo the therapeutic release rate test with HCl instead of lemon juice and with much more than 15 beads per environment (maybe 40-50 each). For the video, we will also show the beads before they are submerged into the solutions to reassure that the beads are similar in size and dye concentration before the tests.
Friday, May 27, 2016
Friday, May 20, 2016
Week 8: 5/20 - 5/26
This week, we continued testing from the previous week. A control group of ordinary loaded calcium alginate beads were placed in a neutral and acidic environment as well; it serves as a baseline for our chitosan-coated beads. A video demonstrating the diffusion rate was recorded as the final deliverable, but if there is time, we would like to increase the number of beads tested to achieve more visible results. We also worked on the final presentation; currently, only the introduction and methodology were completed.
As it can be seen, the alginate beads diffuse the fastest in water. Alginate beads also diffuse at a reasonable rate in lemon juice, although slower than water. Chitosan beads diffuse a little bit in lemon juice, but they don't diffuse at all in water.
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| The four groups: Alginate beads in water, Chitosan beads in water, Alginate beads in lemon juice, Chitosan beads in lemon juice |
As it can be seen, the alginate beads diffuse the fastest in water. Alginate beads also diffuse at a reasonable rate in lemon juice, although slower than water. Chitosan beads diffuse a little bit in lemon juice, but they don't diffuse at all in water.
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| Chitosan Beads in Lemon Juice |
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| Chitosan Beads in Water |
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| Alginate Beads in Lemon Juice |
Friday, May 13, 2016
Week 7: 5/13 - 5/19
This is the second week of experiments and first week of testing. The same procedure as last week was followed to create the chitosan alginate beads. Half of the chitosan alginate beads was placed in 20 mL of water, while the other half was placed in 20 mL of ~ 2 pH lemon juice. The time it took for the dye to diffuse out of the beads was observed.
Friday, May 6, 2016
Week 6: 5/6 - 5/12
This is the first week of experiments. We are doing a preliminary experiment to test our method today during lab. Several chitosan-coated alginate beads were successfully created.
Week 5: 4/29 - 5/5
This week, we ordered our materials for the production of chitosan layered alginate beads. Specifically, we ordered 50 mL of chitosan solution (which we will dilute to 3% w/v), a syringe with size-22 needle, several 50 mL and 100 mL beakers, and filter paper. Everything arrived on 5/5, except the syringe, which will arrive on 5/9. Sodium alginate, calcium chloride, and water will be provided for us in lab. Instead of encapsulating antacids, we are encapsulating food coloring. The rationale behind this change is because antacids are difficult to see, whereas food coloring is easy to detect with the naked eye; this will ease the testing of diffusion rates.
Week 4: 4/22 - 4/28
This week, we wrote a detailed step-by-step procedure (including materials) for the production of chitosan layered alginate beads; more details can be found under the materials & methods tab. Essentially, we will be mixing 3% w/v sodium alginate into 3% w/v calcium chloride dropwise with a size 22 syringe to form small beads. Then, we will stir the beads in antacid solution to encapsulate the therapeutics. Finally, we will dip each bead into chitosan solution for < 1 second and wash them with distilled water to form the polyelectrolyte complex film.
Friday, April 29, 2016
Week 3: 4/15 - 4/21
This week we presented our methodology of our alginate-chitosan layered capsule as a PowerPoint presentation. Calcium alginate beads will be created from dripping sodium alginate into calcium chloride solution. Therapeutics will be encapsulated into the beads via rotary die or mixing. Chitosan will be coated on the calcium alginate beads using the Polyelectrolyte Multilayer Method (PEM). Essentially, the beads will be quickly dipped into chitosan solution and washed, forming a thin film of polyelectrolyte complex.