1. Immobilization

1.1 Compare the effect of different immobilization methods on microcapsules’ patterns

We chose three methods to immobilize E.coli. Then we made a pre-test to ensure each method’ feasibility, including immobilization materials and equipment.

1.1.1Procedure

PVA(Polyvinyl alcohol)-SA(Alginate)

1. Pour some solution into beakers.
2. Draw certain amount of 8%PVA-1%SA and add it into 3%BA(Boric acid)-1%CaCl2.

SA(Alginate)

1. Pour some solution into beakers.
2. Draw certain amount of 8%PVA-1%SA and add it into 3%BA(Boric acid)-1%CaCl2.

ACA(Alginate & Chitosan)

1. Pour some solution into beakers.
2. Draw certain amount of 1.5%SA and add it into 100mmol/LCaCl2
3. Throw the microcapsule into 0.3%Chitosan.
4. Throw the microcapsule into 0.15%SA.
5. Use syringe to inject sodium citrate in the microcapsule.

1.1.2 Result

1. Different materials of immobilization

We decided to apply only SA and ACA materials to our experiment, and we will delete step e. of ACA because it’s infeasible.

2. Comparison of syringe and pipet

We decide to apply syringe to our experiment because syringe has a better effect on microcapsules’ patterns than pipet.

1.2 Compare the effect of different preserving temperatures of microcapsules on E.colis' survival

We chose three common preserving temperatures to carry out our experiment, including room temperature 25℃, cooler compartment 4℃, and freezer compartment -18℃.

1.2.1 Procedure

1. 把菌液包埋起來，放置攝氏-18,4,25度的環境中
2. 每隔48小時進行破囊，並取出菌液培養至固態培養基上，後放入攝氏37度的環境中培養
3. 再過48小時後數菌

1.2.2 Result

WE HAVEN’T FINISHED

2. Freeze-dried & Heavy metal absorption of chitosan

2.1 Compare the effect of freeze-dried and oven-dried chitosan on heavy metal absorption

There are many kinds of heavy metal, and here we take Cu(II) ion for example.

2.1.1 Procedure

1. prepare 1.5 g of chitosan
2. add in 0.4 M 50 ml of citric acid
3. use the magnetic mixer at the speed of 100 rpm to mix the mixture for 12~24 hr
4. use the peristaltic pump to drop the mixture into 0.9 M NaOH mixture
5. wait for 72 hr after the reaction
6. after been washed with DI water, put the chitosan-citrate beads into the oven and dry at 35℃ for 24 hr

2.1.2 Result

Table 1: The effect of freeze-dried and oven-dried chitosan on Cu(II) ion adsorption

2.2 Compare the effect of different initial concentrations on chitosan for heavy metal adsorption

2.2.1 Procedure

1. prepare 3.929 g of copper sulphate.
2. add DI water to 1000 ml
3. take out 200 ml of the mixture, and add DI water to 1000 ml
4. add 1 g of freeze dryer-dried chitosan-citrate beads into the different concentration Cu(II) ions mixture, and mix at the speed of 100 rpm
   100 mg/L
   250 mg/L
   500 mg/L
   750 mg/L
   1000 mg/L
5. take samples at 0 hr, 1 hr, 2 hr, 4 hr, 8 hr, 24 hr, 48hr, 72 hr

2.2.2 Result

The higher the concentration is, the better the chitosan-citrate beads’ adsorption will be; but the percentage of adsorption will be lower