TITLE: Pipetting 
AUTHORS: Carlos Goller, Carly Sjogren

[DESCRIPTION]
Overview and Goals
Lab micropipettes allow us to accurately transfer small volumes of liquids. Units to measure small volumes with micropipettes are: microliter (uL) and milliliter (mL). There are 1000 uL in 1 mL). Effectively using lab micropipettes is a valuable skill that takes practice! We will work together to learn and improve our pipetting to improve accuracy. 

After completing this lab you will gain the following lab skills:

Lab safety and proper personal protective equipment (PPE)
Pipetting with micropipettes


[BEFORE_START]
How to use a micropipette - We will practice pipetting small volumes of colorful liquids using micropipettes. We will work together practicing this new skill to improve our technique. Before coming to the lab watch this 5-minute video, How to Micropipette, that demonstrates 3 key pipetting skills: 
How to hold a micropipette
How to set a micropipette to a desired volume
How to use the plunger and ejector of the micropipette to measure a desired volume of a reagent
 

[GUIDELINES]

Reducing waste - micropipette tips - Pipetting best practices dictate that a new micropipette tip should be used every time you pipette a new volume of liquid. This can be very important in avoiding contamination in molecular biology. Unfortunately, this also creates a considerable amount of plastic waste. For this activity, to reduce unnecessary waste, we will reuse tips when only pipetting water. 

[STEPS]
SECTION: Using a pipette
1. To draw up liquid

SECTION: Using a pipette
1.1. Set volume using the volume adjustment wheel

SECTION: Using a pipette
1.2. Press a new tip onto the shaft
SECTION: Using a pipette
1.3. Press plunger TO the FIRST STOP
SECTION: Using a pipette
1.4. Dip tip into liquid 
SECTION: Using a pipette
1.5. Slowly release the plunger to collect liquid into the tip. 
SECTION: Using a pipette
2. To dispense sample
SECTION: Using a pipette
2.1. Touch tip to dispensing container
SECTION: Using a pipette
2.2. Press plunger THROUGH to the SECOND STOP
SECTION: Using a pipette
2.3. Remove tip from liquid then release plunger
SECTION: Using a pipette
2.4. Dispose of tip using the tip ejector
SECTION: Activity 1
3. Read the volumes specified on the Micropipetting Practice Card and use your micropipette to add the correct amount of liquid to each circle. 

 

SECTION: Activity 1
4. Try to pick up all of the liquid without leaving any behind. 

 

SECTION: Activity 1
5. In the blank space at the bottom of the card, pipette 5 µL  of water three times.

 


SECTION: Activity 1
6. On a dry place on your card place 4 µL  water. Add 4 µL  to the same place three more times. 

This is what your card should look like:
 

 

SECTION: Activity 2
7. Preparation of cards and dyes



SECTION: Activity 2
7.1. Add 13.5 µL of blue dye to dot A 

SECTION: Activity 2
7.2. Add 17.5 µL of yellow dye to dot C 

SECTION: Activity 2
7.3. Add 17.5 µL  of red dye to dot E 

After this step, this is what your card should look like:
 

SECTION: Activity 2
7.4. From dot A, pick up 2 µL  and place it on dot F 

SECTION: Activity 2
7.5. From dot C, pick up 4.5 µL  and place it on dot B 

SECTION: Activity 2
7.6. From dot E, pick up 3 µL  and place it on dot D 

After this step, this is what your card should look like:
 
 



SECTION: Activity 2
8. From dot E, pick up 6 µL  and mix it with the volume already present on dot F 
  
SECTION: Activity 2
9. From dot A, pick up3.5 µL and mix this volume onto dot B 

SECTION: Activity 2
10. From dot C, pick up 5 µL  and mix this volume onto dot D 
After this step, this is how your card should look like:
 


SECTION: Activity 2
11. Calculate how much volume (in units of microliters) should now be on each dot: 



 

SECTION: Activity 2
12. Set your micropipette to that volume and pick up each drop one by one and move to the open space at the bottom of your card. Each time you pick up a drop, note if liquid was left behind (code: LB), or if there is any space at the end of your pipette tip (code: S).