The Materials and Methods section in research papers describe your experimental procedures. Unless your entire paper is on methodology, it is perhaps the easiest part of a manuscript to write, because you do not interpret data or reach conclusion. It is a straight forward recounting your approach.

This section should not be too lengthy; some information may be of lesser interest and can be de-emphasized by using smaller print. Sufficient information should be provided so that an interested reader can repeat the experiments. When deciding what information to include in Materials and Methods, bear in mind that a careful reviewer will read this section to judge whether your procedures were sufficient enough to provide a valid answer to the question raised in Introduction. Here are the tips for writing Materials and Methods:

• The name, source, purity, and potency of each material used should be stated. Whenever hazardous materials and dangerous methods were used, the necessary precautions should be stated.
• Experimental conditions are briefly but precisely should be stated.
• Novel methods should be described in detail, but published method should merely be cited by appropriate references to both the original and any published modifications.
• Any major modification of a well-established procedure must be detail.
• The methods of determining quantitative measurements (for example, the concentration of a protein in solution) should be mentioned so that the reader can be aware of possible inherent errors. This information is often overlooked in publications, making it difficult to guess the accuracy of the quantitative measurements.
• Verb in this section are generally written in the past tense. Use of the passive voice is also acceptable, especially as a means of placing emphasis. For instance, Enzyme A was purchased from Sigma, is better than We purchased enzyme A from Sigma.