-
1Making Benedict's Reagent
The easiest way to test the functionality of amylase is to see if it can actively breakdown a di- or polysacchiride into a simple sugar, and that is by utilizing the Benedict's test. This test includes the use of Benedict's reagent, which will change color from a transparent, blue solution to a range of colors between green and brick-red.
In order to make 100 mL of Benedict's Reagent (BR), you will need:
- 17.3g of Na3C6H5O7 (sodium citrate)
- 10g of Na2CO3 (sodium carbonate anhydrous)
- 1.73g of CuSO4 * 5H2O (copper sulfate pentahydrate)
*these chemicals should be weighed out either on watch glasses or on weigh boats*
- distilled or RODI water
- one 100mL volumetric flask OR measuring cylinder
- two 80mL beakers
- two glass stirring rods
- a small funnel
- a bottle or container with a close-fitting seal to store the BR in after making it
- a hot plate or Bunsen burner
- two scoopulas
Once you have these items, the procedure for making the BR is as follows:
1. add 17.3g of sodium citrate and 10g of sodium carbonate to one 80mL beaker
2. add 50mL of distilled or RODI water to the beaker and stir the contents together (can be accelerated by using a burner)
3. in the other 80mL beaker, add 1.73g of copper sulfate pentahydrate
4. add 10mL of distilled or RODI water to the beaker and stir the contents together
5. slowly add the copper sulfate pentahydrate solution to the sodium citrate-sodium carbonate solution, making sure to stir the solutions together after each small increment is added
*for the following steps, take care to not exceed 100mL of mixture, as this will tamper with ruin the batch
6. rinse the stir rod and beaker used for the copper sulfate pentahydrate solution using distilled or RODI water and pour the rinse into the combined solution to ensure that all of the copper sulfate pentahydrate is added
7. add the combined solution to a 100mL volumetric flask or measuring cylinder using a funnel
8. rinse the beaker and the funnel using distilled or RODI water and pour the rinse into the volumetric flask or measuring cylinder
9. fill the remaining solution with water until it reaches the 100mL mark exactly
10. cap the solution and mix the contents together thoroughly by inverting multiple times
11. transfer the solution into a separate container labeled "Benedict's Reagent" and seal tightly before storing
Once you have done this, you now have Benedict's Reagent and are able to carry out a Benedict's Test to test the presence of reducing sugars and, subsequently, the activity of amylase. It is best to use Benedict's Reagent promptly after making it, but if you need to store it for later, I recommend a sealed container and refrigeration to ensure its stability and preservation.
-
2Testing Surfactants with Benedict's
Since Cu2O nanoparticles (the product of the Benedict's reaction that provides the brick-red color of a positive result) are unstable, we will be attempting to stabilize these with several surfactants. We will be using several surfactants in the presence and absence of the starch 1) to test the ability of each surfactant to remain stable within Benedict's reagent (BR) and 2) to ensure that the starch mixture won't react with BR on their own without amylase.
Below is the list of surfactants used and the quantities used to make the corresponding concentration in 50mL of water:
A) Polysorbate 20 - 0.028mL (0.0005M)
B) Polysorbate 80 - 0.031mL (0.0005M)
C) Glycerol monostearate - 0.0090g (0.0005M)
D) Triton X-100 - 0.084mL (0.0005M)
E) Lauric acid - 0.0101g (0.001M)
F) Dodecanol - 0.0093g (0.001M)
G) Diaminododecane - 0.0100g (0.001M)
H) Brij L-4 - 0.095mL (0.0005M)
J) Polyvinylpyrrolidone (PVP) - 0.0556g (0.0005M)
In order to test the ability of each surfactant to remain stable in BR and to stabilize Cu2O nanoparticles, we will perform two tests parallel to one another. For each surfactant, we will make a solution of just BR and surfactant and we will make a solution of BR, surfactant, and starch. The results of the former test ideally should show that the BR remains unchanged, meaning that the surfactant did not react with the BR. The results of the latter test ideally should show minimal color change, maintaining its predominant light blue color.
To test the stability of the surfactants in the BR, the procedure is as follows:
1. add 4mL of BR to a 20mL glass vial
2. using a hot plate, bring the solution to a boil
3. remove the vial and add the premeasured Polysorbate 20 (A)
4. mix the solution and observe any change in the solution
5. cap and label the vial and store it in a cool, dark place
6. repeat steps 1-5 for the remaining surfactants (B-J)
To test the starch in BR, the procedure is as follows:
1. add 4mL of BR to a 20mL labeled glass vial
2. using a hot plate or Bunsen burner, bring the solution to a boil
3. add the premeasured Polysorbate 20 (A, see above)
4. add 0.4mL of test sample (made by combining 100mL of DI water, 4.5850g flour, and 1.287mL of fruit pectin)
5. mix the solution together and observe any color change
6. return to the hotplate or Bunsen burner and bring to a boil
7. remove the vial and mix the solution, observe any color change
8. cap the vial and store it in a cool, dark place
9. repeat steps 1-8 for the remaining surfactants (B-J)
Once both of these procedures are complete, leave the solutions sitting for 24 hours to observe if the color has changed in that period of time. Be sure not to subject the solutions to too much movement or environment change while they are resting, as this may disturb the solutions and could disrupt the stability of the BR and the nanoparticles. Take pictures before and after to see any change.
After these mixtures were left overnight, we found that a few of the surfactants would not be viable for the test and excluded them from further testing. We moved forward with Polysorbate 20, Polysorbate 80, glycerol monostearate, Triton X-100, and PVP.
-
3Benedict's Reagent, Successful surfactants, and Reducing Sugar
This part of the experiment happened in two stages: testing to see if Benedict's Reagent (BR) would still function when diluted; and seeing how the surfactants are at stabilizing the copper oxide nanoparticles to prevent them from oxidizing.
The first part was done under the thought that if there is less BR present in the reaction, the rate of reaction will be slower and the nanoparticles produced from the reaction would be smaller. We wanted to see how far we could dilute the BR and still have a positive result when introducing it to a reducing sugar, so we tested a 1:2 part dilution, a 1:5 part dilution, and a 1:10 part dilution.
To test the BR dilutions, the procedure is as follows:
1. using a pipette, add 5mL of distilled or RODI water to a 20mL glass vial labeled 1:2 dilution
2. using a pipette, add 5mL of BR and mix together to make the 1:2 part BR dilution
3. using a pipette, add 8mL of distilled or RODI water to a 20mL glass vial labeled 1:5 dilution
4. using a pipette, add 2mL of BR and mix together to make the 1:5 part BR dilution
5. using a pipette, add 9mL of distilled or RODI water to a 20mL glass vial labeled 1:10 dilution
6. using a pipette, add 1mL of BR and mix together to make a 1:10 part BR dilution
7. to make the test sample (1M honey solution), add 70mL of water to a beaker
8. add 14g of pure honey to the beaker
9. stir until the honey has completely dissolved in the water
10. using a Bunsen burner or hot plate, bring the 1:2 part BR dilution to a boil
11. remove the vial and add 1mL of the 1M honey solution
*I chose to photograph and videotape the reactions to see what they looked like and how long it took for each one, but that is not necessary for the procedure, though it is nice to look back at for logistics and filing*
12. repeat steps 10 and 11 with the 1:5 and the 1:10 part BR dilution
For all of these tests, the BR reacted with the honey solution to produce a dark orange color. The particulate matter was the most fine in the 1:10 part dilution, so we are moving forward with that, as it has the smallest nanoparticles produced with the most diluted sample of BR.
For the next stage of this experiment, we are testing the surfactants that we tested with starch earlier (see above instructions) and their ability to stabilize the copper oxide nanoparticles in solution after the BR reaction takes place. This was done using Polysorbate 20, Polysorbate 80, Glycerol monostearate, Triton X-100, and PVP, each mixed into BR, followed by the addition of a 1M corn syrup solution.
To test the surfactants in a BR and corn syrup solution, the procedure is as follows:
1. add 45mL of distilled or RODI water to a 100mL beaker
2. add 5mL of BR to the beaker (this will make a 1:10 BR solution)
3. vacuum the gas out of the BR solution (*this step is recommended, as it helps to stabilize the copper oxide from oxidizing further and precipitating out of solution*)
4. immediately after vacuuming, add 10mL of the sample into five 20mL glass vials with a lid and screw the lid on tightly
5. weigh out all of the surfactants (0.5mM of each)
a. Polysorbate 20 - 0.0061g
b. Polysorbate 80 - 0.0066g
c. Glycerol monostearate - 0.0179g
d. Triton X-100 - 0.0324g
e. PVP - 0.0111g
6. add 50mL of water to a 100mL beaker
7. add 9g of corn syrup and stir until the corn syrup is completely dissolved in the water
8. label each of the five 20mL glass vials with the surfactant to be used
9. bring the 'Polysorbate 20' BR solution to a boil using a Bunsen burner or a hot plate
10. remove from heat to add the premeasured Polysorbate 20 to the vial and mix
11. add 1mL of the 1M corn syrup solution to the vial and mix
*I chose to videotape the reactions to see what they looked like and how long it took for each one, but that is not necessary for the procedure, though it is nice to look back at for logistics and filing*
12. repeat steps 9-11 for the remaining surfactants
13. take pictures of the completed reaction to compare the solution to a later time to prove stability
14. store in a dark place overnight or for 24h
15. take pictures of the mixtures again to see if each of the solutions' nanoparticles were stabilized by the present surfactants
-
4Benedict's Reagent with Corn Syrup and Mixed Surfactants
To further test the successful surfactants (Polysorbate 20, Polysorbate 80, glycerol monostearate, and PVP ; Triton X-100 was omitted from further testing as the other surfactants proved to be more stable), we combined them to see if they would act together to stabilize the copper oxide nanoparticles. We decided to test a mixture of Polysorbate 20, glycerol monostearate, and PVP and a mixture of Polysorbate 80, glycerol monostearate, and PVP, all at a concentration of 1mM with the exception of glycerol monostearate, as it is less soluble in water, so we only added 0.15g as this was all that could dissolve fully in the solution.
To test the mixed surfactants in a BR and corn syrup solution, the procedure is as follows:
1. add 32.4mL of distilled or RODI water to a 100mL beaker
2. add 3.6mL of Benedict's Reagent (BR) to the beaker (this will create a 1:10 BR solution)
3. vacuum the BR solution
4. immediately after vacuuming, add 18mL of the solution to two 20mL glass vials with a lid and screw the lid on tightly
5. weigh out all of the surfactants (1mM of each except glycerol monostearate)
a. Polysorbate 20 - 1.1145mL
b. Polysorbate 80 - 1.236mL
c. Glycerol monostearate - 0.15g
d. PVP - 2.2229g
6. add a, c, and d to a 100mL beaker filled with 50mL of water and add b, c, and d to a 100mL beaker filled with 50mL of water to create two surfactant mixtures
7. add 50mL of water to a 100mL beaker
8. add 9g of corn syrup and stir until the corn syrup is completely dissolved in the water
9. label each of the 20mL glass vials with the surfactant mixture to be used
10. bring the 'Polysorbate 20, glycerol monostearate, PVP' BR solution to a boil using a Bunsen burner or a hot plate
11. remove from heat to add the premeasured Polysorbate 20, glycerol monostearate, PVP mixture to the vial and mix
12. add 1mL of the 1M corn syrup solution to the vial and mix
*I chose to videotape the reactions to see what they looked like and how long it took for each one, but that is not necessary for the procedure, though it is nice to look back at for logistics and filing*
13. repeat steps 10-12 for the remaining surfactant mixture
14. take pictures of the completed reaction to compare the solution to a later time to prove stability
15. store in a dark place overnight or for 24h
16. take pictures of the mixtures again to see if each of the solutions' nanoparticles were stabilized by the present surfactants
The same process was done and tested at a lower temperature to test the reaction at the optimal temperature of amylase (60-65C) and at a lower concentration to see if the reaction still occurs.
To test the mixed surfactants in a BR and corn syrup solution at lower temp. and conc., the procedure is as follows:
1. add 32.4mL of distilled or RODI water to a 100mL beaker
2. add 3.6mL of BR to the beaker (this will create a 1:10 BR solution)
3. add 34.2mL of distilled or RODI water to another 100mL beaker
4. add 1.8mL of BR to the beaker (this will create a 1:20 BR solution)
5. vacuum both BR solutions
6. immediately after vacuuming, add 18mL of each solution to four labeled 20mL glass vials with a lid and screw the lid on tightly
7. weigh out all of the surfactants (1mM of each except glycerol monostearate)
a. Polysorbate 20 - 1.1145mL
b. Polysorbate 80 - 1.236mL
c. Glycerol monostearate - 0.15g
d. PVP - 2.2229g
8. add a, c, and d to a 100mL beaker filled with 50mL of water and add b, c, and d to a 100mL beaker filled with 50mL of water to create two surfactant mixtures
9. add 50mL of water to a 100mL beaker
10. add 9g of corn syrup and stir until the corn syrup is completely dissolved in the water
11. label each of the 20mL glass vials with the surfactant mixture to be used and the concentration of BR
12. heat the 'Polysorbate 20, glycerol monostearate, PVP, 1:10' BR solution to 60-65C, being careful not to let get more than 65C
13. remove from heat to add the premeasured Polysorbate 20, glycerol monostearate, PVP mixture to the vial and mix
14. add 1mL of the 1M corn syrup solution to the vial and mix
*I chose to videotape the reactions to see what they looked like and how long it took for each one, but that is not necessary for the procedure, though it is nice to look back at for logistics and filing*
15. repeat steps 12-14 for the remaining surfactant mixtures at each BR dilution
16. take pictures of the completed reaction to compare the solution to a later time to prove stability
17. store in a dark place overnight or for 24h
18. take pictures of the mixtures again to see if each of the solutions' nanoparticles were stabilized by the present surfactants
Since the lower concentration and lower temperature both still yielded successful results, we also tried diluting the BR with both water and propylene glycol to see if that would help to further suspend the copper oxide nanoparticles. Additionally, more PVP was added (1mM -> 5mM).
To test the mixed surfactants in a BR and corn syrup solution at lower temp. and conc. and the addition of propylene glycol, the procedure is as follows:
1. add 27.36mL of distilled or RODI water to another 100mL beaker
2. add 6.84mL of propylene glycol
3. add 1.8mL of BR to the beaker (this will create a 1:20 BR solution with 20% of the water replaced with propylene glycol)
4. vacuum the BR solution
5. immediately after vacuuming, add 18mL of each solution to two labeled 20mL glass vials with a lid and screw the lid on tightly
6. weigh out all of the surfactants (1mM of each except glycerol monostearate and PVP)
a. Polysorbate 20 - 1.1145mL
b. Polysorbate 80 - 1.236mL
c. Glycerol monostearate - 0.15g
d. PVP - 10.54g
7. add a, c, and d to a 100mL beaker filled with 50mL of water and add b, c, and d to a 100mL beaker filled with 50mL of water to create two surfactant mixtures
8. mix over heat until both mixtures are fully dissolved
9. add 50mL of water to a 100mL beaker
10. add 9g of corn syrup and stir until the corn syrup is completely dissolved in the water
11. label each of the 20mL glass vials with the surfactant mixture to be used and the concentration of BR
12. heat the 'Polysorbate 20, glycerol monostearate, PVP, 1:10' BR solution to 60-65C, being careful not to let get more than 65C
13. remove from heat to add the premeasured Polysorbate 20, glycerol monostearate, PVP mixture to the vial and mix
14. add 1mL of the 1M corn syrup solution to the vial and mix
*I chose to videotape the reactions to see what they looked like and how long it took for each one, but that is not necessary for the procedure, though it is nice to look back at for logistics and filing*
15. repeat steps 12-14 for the remaining surfactant mixture
16. take pictures of the completed reaction to compare the solution to a later time to prove stability
17. store in a dark place overnight or for 24h
18. take pictures of the mixtures again to see if each of the solutions' nanoparticles were stabilized by the present surfactants
-
5Creating the RF Faraday Cage
For the STEP and STL files of the Faraday cage (AKA the Box) that we are making for this experiment, please see the Files tab. The Box was made specifically for this experiment to do a few things: to hold a quartz cuvette (dimensions 45x12.5x12.5 mm from Amazon); to allow for a through-hole LED and photodiode to be interchangeably included depending on the required peak frequency; to allow for the HackRFOne radio emitter through-hole style mount to center its emission on the cuvette; to hold a film in front of the LED to help filter the light coming through (optional); to allow for a temperature probe to be place into the cuvette. The dimensions of the bottom of the Box are 4x4x5.25 cm and the lid is slightly larger to fit on top of the bottom. The Box is to be machined out of Brass to allow for a proper seal on the radio frequency to prevent excess noise release.
The link to the OnShape project is here: https://cad.onshape.com/documents/7c48503f6a6e51b58850620d/w/6de86e682861b47d2f8f62c2/e/9b430e32444907e523e9103e?renderMode=0&uiState=655502a305edc3715884b471
Discussions
Become a Hackaday.io Member
Create an account to leave a comment. Already have an account? Log In.