Question

1) You have extracted your targeted plasmid from Milariuza. equilirus in your home. Because you do not have an expensive nanodrop machine, you decided to run a gel to determine the concentration of your sample. However, you also don’t have Tris-acetate, thus can’t make any TAE buffer. Being a smart student, you realize you can simply make 1X TBE buffer instead of 1X TAE buffer for your experiment. You will need 800ml TBE buffer for both making the gel and use it as a running buffer. You do not have any access to pipettes because you left them at school, and you only have large graduate cylinders. This means that any measurement below 10ml is inaccurate. The balance you have can only measure accurately above 100mg. Please show all works.

                                 Recipe for 5X TBE buffer                    Stock Materials

500mM Tris-Borate                                50M Tris-Borate

10mM EDTA                                        EDTA (MW ? 300)

5%NaOH                                              NaOH (MW ? 40)

Answer 1

In order to make 800 ml of 1 X TBE buffer from 5 X TAE following volume is required.

5 X * Y= 1X * 800

Y= 1X* 800/ 5X

Y= 160 ml of 5 X TBE required.

For this purpose we will make 200 ml of TBE and further dilute it.

As give 5 X TBE 500 mM or 0.5 M buffer of tris borate is require. Here stock solution is 50 M.

50 M* X= 0.5 * 200

X= 100/50

X= 2ml

This volume we cannot measure due to limitation of measuring cylinder. Now if we take 10ml of tris-borate then how much volume of 500mM or 0.5 M will make.

50 *10= 0.5*X

500/0.5= X

1000= X

Minimum 1000 ml or 1 lit volume we have to take

Now calculate each component according to 1000 ml or one liter.

10 mM = wt in gram* 1000/ Mw * volue in ml

10mM= wt in gam *1000/ 300 *1000

300*10 *10^-3= wt in gra

3000 mg or 3gm= of EDTA is require for 1000 ml or 1lit.

This can be use because weighting machine can measure above 100mg.

Here 5 % NaOH is required. This is percentage that required here molecular weight is not required.

For 100 ml 5 gm of NaOH is required

For 1 ml how much NaOH required = 5/100

For 1000 ml how much is reuired= 5* 1000/100

NaOH is 50 gm is required.

Mix all the component and dissolve them and at last make final volume 1000ml

From this take 160 ml and add 640 ml will make 1X TBE solution.