Guidelines for Biochemistry Laboratory Notebooks
Dr. Thomas Wiese

A laboratory notebook is a permanent legal record of a scientist's investigations and is useful only if it contains sufficient information to enable someone else to reproduce the results of any experiment described in the notebook. The following guidelines for good notebook keeping should be followed.
 

1. The lab notebook is a permanent record. Use a bound notebook, not a loose-leaf or spiral notebook. In addition, we will be using carbon-copy notebooks. This type of notebook is most effectively obtained through the Chemistry/Preprofessional club (341 TH).
2. Number the pages sequentially in the top outer corner beginning with the first page. Notebooks purchased through the chem club are printed with page numbers and are therefore recommended.
3. Make all entries in ink, directly into the lab notebook. Do not use pencil. If a mistake is made, draw a single line through the mistake and write the correction above the line. Do not obliterate or use whiteout. Notes found taken in the lab on odd pieces of paper will be confiscated.
4. Begin the notebook with a table of contents. Leave the first 1 or 2 pages blank and enter the title and page number of each experiment when you perform it. The title can be the same as that found on the lab separate or you can write a more descriptive one.
5. Use a new page for each experiment, and preferably start a new page each day. Particularly with research notebooks, this aids in finding information when the time for publication arises.

Required Format


A. Heading in the upper right-hand corner: Name of student and lab partner if appropriate (usually not) Title of experiment Date experiment was begun (each subsequent page should have the date on which the experiment was performed).

B. Statement of purpose: Briefly describe the purpose of the experiment. Try to understand the author's intention for including this as an educational experience. What principles or skills can be gained from performing this experiment? I want only one or two sentences here.

C. Describe the procedure followed but: There is no point in transcribing a procedure already written in detail in the lab manual. Instead, write it out in such a way that you can follow your notebook instead of the lab manual. You should write the essence of the procedure in one sentence using your own words. If any changes are made, these should be described in detail in this section. You should also include one sentence on the expected results.
Example: Glucose, water, and DNS are mixed and incubated in a boiling water bath as described in lab manual, experiment one, with the exception that tubes were run in duplicate. A color change indicates the presence of glucose proportional to the color change.

D. If the experiment involves a known chemical reaction, the structures of the reactants and products should be drawn out in a balanced equation of the reaction.

E. Record any observations, e.g., color changes, temperature changes, formation of a precipitate. Next to an observation describe your interpretation of it. It is usually advantageous to construct tables prior to the experiment to facilitate recording of data and observations, such as:
 
Tube mL Glc mL H2O mL DNS %T A540 nm
1 0 1.0 1.0
2 0.2 0.8 1.0
3 0.4 0.6 1.0

F. Show your calculations. If there are many calculations that are the same, show one set and present the other results in a table.

G. Summarize your results in tabular or graphical format if possible. Otherwise, write a summary sentence.
Example: Figure one shows the standard curve produced in this laboratory. Using this standard curve, it is concluded that Unknown A has a concentration of 120 µg/mL.

If a graph or other record is made and attached to the white page, some type of facsimile must be attached to the yellow page and turned in.

H. Answer assigned questions.

6. When appropriate, turn in products with a neatly printed label on the vial listing:
Lab and experiment- such as 662L-504
Name of the compound
Student's name Date

7. In contrast to organic chemistry, where information is expected in only one place, I encourage you to duplicate information, as you will have to do in a professional presentation.

•You are required to turn in the yellow pages of any work done at the conclusion of that laboratory period. Only those results and observations turned in at the end of the laboratory period may be used in the completion of the remaining portions of the laboratory writeup. Writeup of conclusions, graphs, etc. are due no later than the beginning of the following laboratory period.

•Notebooks will be turned in at the end of the semester for a final examination. At that time I will be examining things like the table of contents being up to date, etc.

Tables


Tables require careful labeling of all data presented to avoid confusion.
1. Every row and column should have an appropriate heading or label, and any codes or abbreviations should be explained in a footnote to the table.
2. The units of all measurements should be specified. If the condition is the same for all tabulated data, this is indicated at the top of the column.
3. It is not wise to put too much data into a single table. Use of several tables will emphasize or highlight the important aspects of the data.
4. Do not include more significant figures than are justified by the accuracy of the determinations.
5. If mean values are reported, some accepted measure of the range should be indicated, along with the number of individual observations contributing to the mean value.

Graphs


Graphs are used to illustrate quantitative data and can quickly indicate the relationship between two or more variables and any special trends that might be present. There are several important rules for making good graphs.
1. Use graph paper, preferably 10 or 20 lines/cm.
2. Always label both the y-axis (ordinate) and the x-axis (abscissa). Place the dependent variable(s) [what is being measured] on the ordinate and the independent variable [what is being varied] on the abscissa. If possible, enclose the top and right-hand sides of the figure.
3. Choose sets of coordinates that are easy to read and have major divisions expressed as integers, multiplied by the appropriate power of 10, if necessary (or a mixture of integers and decimals, if more convenient).
4. Select scales that have uniform intervals and distribute the data over most of the area of the graph rather than having the data compressed into one region of the graph.
5. Clearly indicate experimental points. Circles can be used to indicate the uncertainty (error) of the measurement in both variables. Vertical lines (error bars) can be used to represent uncertainty in the dependent variable.
6. Keep the number of lines on a single graph to a minimum. Assign distinct symbols (e.g., circles, open and solid, triangles, open and solid) to each set of data. Symbols should be explained in the legend to the graph.
7. Prepare a title that describes the graph and gives enough experimental detail to permit the material to stand on its own. Readers should be able to understand what the data in the graph mean without reference to the text.