The Five Essentials of Organizing Laboratory Samples

If you look closely, there’s a scenario that plays out frequently in labs across the world: A scientist sits hunched over dry ice searching exhaustedly through frozen boxes for one sample that has disappeared into the abyss. The tube or specimen in question was likely catalogued at some point in time. But, between then and now it was likely rearranged, thrown out, or most frustrating of all, mislabeled.

If there is anything that scientists hate more than losing potential data, it’s wasting time. Searching through a packed freezer can potentially take days. And, sometimes, the misplacement of a key sample delays experiments by several weeks or more. You can be sure that “I lost my sample” goes over about as well in lab meetings as “my dog ate my homework” did in grade school (or undergrad, for some).

To avoid the above scenario, both novice and experienced researchers (that means you!) could use a primer or a refresher on some cardinal rules of sample organization.

So, without further adieu, here are the five organization essentials for maintaining lab samples.

1. Develop a system

When dealing with a large number of samples that you will store for the foreseeable future, do yourself the favor of developing a simple system for cross-referencing the identity of each sample.

For example, to save time labeling the tubes themselves you could just label each tube numerically with the date on the cap. Then, keep a more detailed description in your lab notebook (i.e. including location in the freezer, number of tubes in dataset, etc.) that corresponds to the date and sample number on the tube.

Remember to keep the template posted around your bench or inside your office to ensure fidelity from day to day.

 2.  Always Cross-reference

We all know that writing in your lab notebook can become an afterthought during a busy day of blaring timers, scattered thoughts and numerous experiments. However, recording your labeling system into your lab book and documenting the identity of the sample as you collect it will pay dividends when returning to it months or years later. This system of redundancy will act as a cross-referencing tool to limit the amount of misidentification and undocumented re-arrangement of samples.

However, for this to work, you must label properly.

3.  Proper Labeling

Label clearly and label concisely. This goes without saying. But since it goes without saying, it is rarely taught. There are more than a few new graduate students that label their tubes with non-waterproof or ethanol-proof markers.

To make sure you can always read your labels:

• Label with a fine-point marker
• Use a marker that is waterproof and ethanol resistant
• Develop a short hand system for numbering to prevent trying to squeeze too much info on the label
• If your sample has frost collected on the label area, dab it lightly with a dry wipe. If the writing is still legible, re-record it in your book and then proceed to wipe off the frost

4.  Carefully Arrange Samples

As tempting as it may be to drop your labeled samples into the nearest available slots in your freezer boxes, record the samples that are stored in each box and record all subsequent changes. This maintains the integrity of your labeling system while allowing easy and direct access to your samples.

5.  Stay Consistent

Perhaps the most important suggestion is to stay consistent. Always maintain consistent and vigilant labeling and organization of your painstakingly collected samples. Remember, every step you take to prevent mislabeling or misplacement will pay dividends in the long run.

Have any interesting tips to add? We would love to hear them in the comment section below!