Lab Notebooks

Lab Notebooks & Record Keeping:

As you move from labs with pre-defined protocols into research (where you have to define your own protocol), your lab notebook becomes increasingly important as both a place to plan out your work and where you keep an accurate and complete record of what you’ve done. When you are designing your own experiments, careful planning ahead of time ensures that your time in lab is well spent and productive and minimizes both potential safety hazards and waste of materials. That said, research is inherently pushing the boundaries of knowledge. As such, planning will only take a project so far results are frequently not something that you can exactly predict when you’re working with new systems. Moreover, some of the most interesting results are those which we didn’t anticipate and can lead to discovery.

Keeping an accurate record of your results is what lets you go back and figure out what happened when a result is unexpected. Details that may not have seemed important at the time can be what explains why two seemingly similar experiments can lead to different results. Additionally, as scientists we frequently have to refer back months (or even years) to compare new data against old data, as well as to refer to protocols to write up our results. As such, your lab notebook should be updated constantly during lab to ensure that you are writing down exactly what you’re doing- sometimes it may vary slightly from what you planned on doing, and that difference may be key later. As a general rule, write everything down. If you aren’t sure whether a detail should be recorded or not, you should err on the side of writing it down! You may not need it in the future, but if you do you will be very glad you have it. Similarly, every entry should have a date and every page should be numbered.

A good, complete, notebook entry for an experiment contains three general sections of information: things done before lab, things done during lab, and things done after lab. More specifically, the following sections are frequently used:

1. Introduction, Protocol, Background & References (Before Lab)

a. Before you begin working in lab, you need to lay out what you’re planning to do, and any necessary background information.

b. This should include the title of the experiment, any group members you’re working with, a brief description of the goals of the project.

c. It should also contain any protocols or procedures you are planning to follow, or details of experiments you’ve designed.

d. This should also have a section (as needed) detailing hazards and properties of any new chemicals or compounds you’re working with.

e. Finally, if you’re basing your work off of something in the literature, you should reference it.

2. Data & Observations (In Lab)

a. As you perform an experiment, you will have major and minor deviations from procedure- each of these should be clearly noted in your lab notebook. All exact amounts of reagents used, any measurements taken during lab, and any changes to reagent types or formulations should be noted specifically.

b. Some of the most important data in a lab is qualitative- note your observations and thoughts as you progress through an experiment. Color changes, difficulty solubilizing materials, and any other things you notice can be extremely helpful in troubleshooting a project down the road.

3. Calculations and Data Analysis (In Lab & After Lab)

a. A good lab notebook does not stop with experimental data. Consistent calculations and data analysis is just as important to your final conclusions, and the methods and values you use should be noted in your lab notebook, along with a brief description of any analytical methods you employed (i.e., data fitting methods or equations in OriginPro).

b. Additionally, it’s often a good idea to keep physical copies of data generated (plots, graphs, pictures of gels, etc.) in your notebook along with the experiment to refer back to.

4. Discussion and Conclusions (In Lab & After Lab)

a. After you have finished your data analysis, you should take the time to write some brief points of discussion and conclusions. These can draw attention to observations that may explain aberrant data or may point out new directions that could shed light on a question that came up while you were working. 

In addition to keeping good records in your lab notebook, you should make sure that you are consistent in storing and organizing digital data: files should be saved consistently (date_experiment_name), and the file name should always be recorded in your lab notebook so you (or someone else) can find it. 

Most of the work you are doing this semester will be multi-week projects and will be done with partners: your lab notebook isn’t just a record for you to follow but is also a record that will be useful to your classmates. Make sure you organize your notebooks such that they are easily followed to someone else reading through them- especially by making sure you keep an updated and accurate table of contents.