Stock solutions

70% Ethanol (1L)

736 ml 95% ethanol. Bring up to 1 L with nanopure water.Don’t autoclave.


EDTA 0.5 M


To prepare 500 ml, 0.5M EDTA pH 8.0: Add 84 g of disodium EDTA•2H2O to 300 ml of nanopure H2O. Stir vigorously on a magnetic stirrer. Adjust the pH to 8.0 with NaOH (approx. 10 g of NaOH pellets). Bring up to volume with nanopure H20. Dispense into aliquots and sterilize by autoclaving. The disodium salt of EDTA will not go into solution until the pH of the solution is adjusted to approx. 8.0 by the addition of NaOH.


6N HCl


Concentrated hydrochloric acid is 12N=12M. N = M x replaceable H

so for HCl, N=M but for H2SO4, N= 2 x M


Wear safety goggles and gloves. To make a stock solution of 12N HCl pour the acid in slowly. The concentrated HCl will fume. be certain to do this under a hood that will exhaust the fumes. Then add an equal amount of the acid to the water. Do not autoclave.

dilute stock HCl 1:1 with nanopure H2O. Add 500 mL of 12N HCl (adding 500 mL HCl to 500 mL H2O)


1 N HCl


8.6 ml concentrated HCl. Bring up to 100 ml with nanopure water.


10N NaOH


The preparation of 10 N NaOH involves a highly exothermic reaction, which can cause breakage of glass containers. Prepare this solution with extreme care in plastic beakers. To 800 ml of H2O, slowly add 400g of NaOH pellets, stirring continuously. When the pellets have dissolved completely, adjust the volume to 1 liter with H2O. Store the solution in a glass container at room temperature. Sterilization is not necessary.


5M NaCl


To prepare 1 liter of a 5 M solution: Dissolve 292 g of NaCl in 750 ml of nanopure H2O. Adjust the volume to 1 liter with H2O. Dispense into aliquots and sterilize by autoclaving. Store the NaCl solution at room temperature.


1 M Tris-Cl


To make 1 liter, dissolve 121g Tris Base in 750 ml of H2O. Adjust pH to the desired value by adding approximately:


pH = 7.4 about 70 ml of concentrated HCl;

pH = 7.6 about 60 ml of concentrated HCl;

pH = 8.0 about 42 ml of concentrated HCl


 6X Sample Loading Dye


Bromophenol Blue      0.25%

Xylene cyano FF          0.25%

Ficollâ 400                 15%

Tris-HCl (pH 7.5)       10 mM

EDTA (pH 8.0)            50 mM


1 kb Plus DNA Ladder (1.0 mg/ml), 250 mg


Stock                                 30 ml

6X Loading Dye                50 ml

dH2O                                220 ml



Formulation for Lactophenol, Lactophenol BLue and Cotton BLue

From Suzanne Segner


Phenol (liquid) 20 mls

Lactic Acid 20 mls

Glycerol 40 mls

Distilled water 20 mls


Mix well, stirring slowly on stir plate.



Storage and Shelf Life

Lactophenol Blue Solution should be stored at room temperature and protected from light. Under these conditions it have a shelf life of 52 weeks from the date of manufacture.


For LACTOPHENOL BLUE add 0.05% Trypan blue

Stain with 1 to 2 drops of lactophenol blue solution and cover with a coverslip. Examine under the microscope after about 2 minutes.


for COTTON BLUE add 0.05% of Aniline BLue (Stir for disolve)



TE Buffer




1. 10 nM Tris HCl (pH 8, 1M stock) (1mL Tris/100mL water)

2. 1 nM EDTA (.5M stock) (.2mL EDTA/100mL water)

3. Pure water




1. Mix contents in beaker

2. Add to Wheaton Bottle(s)

3. Autoclave, cycle 1




Tris Base 54.0 g

Boric Acid 27.5 g

0.5 M EDTA (pH 8.0) 20 ml


1. Mix contents in beaker. Make up to 1 L


Extraction Buffer


CTAB Extraction Buffer, 100 mls

20 mls 1M Tris, pH 7.5

28 mls 5M NaCl

4 mls 500mM EDTA, pH 8.0

2 grams CTAB (or CDAB)


Mix all of the above, add just enough ultrapure water to make up to 100 mls. Store at room temperature.

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