HOW TO KEEP A LABORATORY BOOK
INTRODUCTION

Lab books are a property of the lab. A lab book is used to record what is done in
the lab as the experiments are performed. The exact format may vary, but all lab
notebooks should be clearly written and comprehensive in order to allow any
other person to repeat the experiment without any other source of information.

In principle your lab book is a legal document that can be used as evidence of
your work in a court of law.

It is a scientific document therefore you should avoid writing in 1st, 2nd person.
Instead of “I loaded 10μl..” write “10 μl were loaded…or…add 10 μl to the mix”

Always keep ONE lab book and write in ink so that if there are questions about
the validity of your findings, you can prove that the work is original and was not
falsified.

Even if you make mistakes you should not use eraser. If you need to correct a
mistake, strike a single line through the error example: RNA from human mouse.
Different colored pens can be used to differentiate data, notes, drawings, graphs,
and calculations from one another

You should NEVER tear a page!!!

You are expected to write your lab book in ENGLISH!

You should write in your lab book EVERY DAY and not once a week about the
last week’s experiments. WRITE WHILE YOU ARE DOING THE
EXPERIMENT.
20/10/07
21/10/07
17/10/07
WRONG
Page 1
Page 2
Page 3
.

START by writing
a. the date
b. what you are going to do (brief heading)
c. why you are doing it (purpose of experiment)
d. how you are doing it (method)

METHODS- PROTOCOLS: You should write the method (appropriate
protocol) at least once in order to repeat it when necessary. Next time you repeat
the method you can write “repeat RNA extraction according to protocol” you do
not have to re-write the whole protocol every time BUT you should clearly
indicate any adjustments you make to it i.e: volume changes, different enzyme
used etc.
EXAMPLE
Τuesday 30 November 2007
Reverse transcription for samples #C1 and #C2
Purpose: make cDNA for controls #1 and #2
Mix : RNA (used 2γ)
ALWAYS write the
concentrations of the
reagents you are using
2 ul
Rand. Hexamers (50ng/ul)
2 ul
dNTPs mix (10mM)
4 ul
DEPC-water
8 ul
Total volume 16 ul
And add ….RTase mix after RNA denaturing
RTase mix: 10x RT buffer (stratagene)
2 ul
RNase inhibitor (40u/ul)
RTase
1 uλ
1 ul
TOT VOL.
4ul
Programme
1) 72oC for 4 min: denature of RNA
Stop reaction and put tubes on ice and add RTase mix
2) 42oC for 60 min
3) 90oc for 10 min
4) 4oC forever
PCR reaction
Tube 1: template #C1 +mix
Tube 2: negative control
etc……..
Run 2% agarose gel
Lane 1: #C1
Lane 2: negative control
ALWAYS write the
order that you have
loaded your samples

AT THE END OF EACH EXPERIMENT ALWAYS WRITE RESULTS
AND OBSERVATIONS AS WELL AS FUTURE EXPERIMENTS

Attach in your lab book, if possible, gel photos, ELISA reading, otherwise write
down name of file that you have saved your data. ALWAYS BACKUP YOUR
FILES. You do not want to lose your work if the computer crashes!!!!!!
example
Result: No detectable band for VEGF for sample #1
Possible cause: amount of cDNA loaded?
Note: Load more cDNA next time

FAQ: “ How much detail should I put in my lab book?”

Answer: You should be able to understand WHAT you did 6 months ago,
HOW and WHY and more importantly another person should be able to
understand your work just by reading your lab book.
Just think that when writing your PhD thesis you will have to write about
experiments performed 3 years ago!!!!!!!!!!!!!!!!!
«Elephant’s memory does not help!»