E12 Technique

Question 1

What is the E12 solution derived from? What is the E12 technique mainly used for?

Answer 1

 E12 solution is derived from epoxy resin polymer
 E12 technique is mainly used on thin body slices
 The end results has a degree of transparency

Question 2

What does the E12 technique provide?

Answer 2

The E12 technique provides accurate, precise and semi-transparent
sectional preparation which offer excellent visual clarity of gross
structure up to submacroscopic level viewable by naked eyes

Question 3

Composition of the E12 solution:

Answer 3

 E12 (plastination fluid)
 E1 HARDENER
 AE10 (plasticisor)
 AE30 (glass separator)

Question 4

Preparation of the specimen:

Steps 1 & 2:

Answer 4

 Freeze specimen in – 20˚C.

 At this temperature make 3mm slices of the specimen using a band saw

Question 5

Preparation of the specimen

Step 3:

Answer 5

 Each slice is carefully wiped and placed in plastic grids and stabilized with ties

Question 6

Preparation of the specimen

Step 4:

Answer 6

 Leave in a container under running tap water for 24 hours to wash off
formalin

Question 7

DEHYDRATION PROCESS

Step 1:

Answer 7

Dehydration is best done at a temperature of -20°C to minimize shrinkage

Question 8

DEHYDRATION PROCESS

Step 2:

Answer 8

 Immerse the slices/specimens in 20% acetone solution

Question 9

DEHYDRATION PROCESS

Steps 3 & 4:

Answer 9

 The concentration of acetone is gradually increased in units of10% until 100% is reached

 This process takes between 6 – 10 weeks

Question 10

DEHYDRATION PROCESS

Step 5:

Answer 10

 For removal of fat: leave the specimen at room temperature for 48 hours following the final stage of dehydration

Question 11

FORCED IMPREGNATION

Steps 1 & 2:

Answer 11

 E12 solution is prepared

 The specimen is immersed in a container filled with E12 solution and placed in a vacuum tank set at a negative pressure of -1KPL

Question 12

FORCED IMPREGNATION

Steps 3 & 4:

Answer 12

 The presence of bubbles in indicative of acetone being replaced by E12 solution in the specimen

 Impregnation should be complete in 36 hours

Question 13

FORCED IMPREGNATION

Step 5:

Answer 13

The specimen should be left in the vacuum tank until bubbles cease to
form, indicating that the tissue is now fully impregnated

Question 14

EMBEDDING PHASE

Step 1:

Answer 14

 Prepare double glass plate using a gasket and clamps

Question 15

EMBEDDING PHASE

Step 2:

Answer 15

 Prepare a new solution of E12 omitting AE30 and pour between these glass plates

Question 16

EMBEDDING PHASE

Steps 3 & 4:

Answer 16

 Carefully place the specimens in this solution and seal the top
 Leave to set and harden at room temperature for 3 – 4 days

Question 17

EMBEDDING PHASE

Step 5:

Answer 17

 Once set, place in an incubator at 40°C for a further 3 days

Question 18

EMBEDDING PHASE

Step 6:

Answer 18

 On removal from the incubator there should be signs of separation

Question 19

EMBEDDING PHASE

Steps 7 & 8:

Answer 19

 Remove the clamps and trim and polish the edges of the cast of the cast of the embedded specimen

 They are ready for museum display