Barcodes in the Laboratory: A Complete Guide

Understand the role barcodes can play in meeting traceability requirements within your laboratory.

When it comes to laboratory management, it is extremely important to be able to differentiate and organize all samples, reagents and plates.

This task, however, can present many challenges, directly affecting the results of your experiments.

For this reason, a Laboratory Information Management System (LIMS) proves to be an indispensable tool for laboratories that want to maintain the highest level of quality.

By assigning a unique barcode to each item, the LIMS increases traceability within the laboratory. But this function is not as simple as it appears.

So, in this article you will understand the role barcodes can play in meeting traceability requirements within your laboratory.

Why track with barcodes?

To answer this question, you first need to determine which physical elements of your laboratory must be tracked with a unique identifier, such as a barcode.

Generally, barcodes should be used to track any item that could easily be confused with, or swapped for, another physical item.

Clearly, the easiest approach would be to label these items by hand, but this manual process can carry risks.

The use of hand-written labels is discouraged for 3 simple reasons:

1. There may be difficulty reading or understanding what is written;

2. When writing by hand, it is difficult to maintain a consistent pattern, which also increases the risk of human error;

3. Some sample tubes are very small and don’t have enough space for more than a few characters.

Barcode as a solution

Your laboratory certainly has dozens, hundreds or even thousands of samples that must be processed while always ensuring their traceability. And with barcodes, that guarantee becomes much easier to achieve.

Another application of this type of identification is using barcodes to track the 96- or 384-well plates you store, since these plates look very similar when viewed inside a freezer or refrigerator.

Other elements that can be tracked with a unique barcode include:

• Storage boxes or shelves;
• Storage equipment (such as freezers or refrigerators, for example);
• High-complexity test equipment (for example, a sequencer);
• General equipment (pipettes, centrifuges, etc.);
• Computers, laptops or tablets.

By using a unique barcode, you not only guarantee the identification and traceability of each of these samples, but you can also use reading equipment, such as scanners, to automate steps in your process.

This way, it’s possible to eliminate the possibility of human error and increase productivity, generating greater reliability and efficiency.

Automatically generated barcodes

Some LIMS platforms have the ability to automatically generate a barcode for any sample, plate or reagent.

By generating barcodes automatically, you can ensure that this unique identification will always exist, eliminating the possibility of someone forgetting to perform this step of the process.

With an automatic barcode, you can be certain that the generated number will be unique within your LIMS.

Duplicate or similar identifiers lead to incorrect sample association, and incorrect data and results.

Even when caught along the way, duplicate or similar identifiers waste time and rework in trying to determine which item is specific to which.

Multiple identifiers for the same sample

It’s common for some elements of your laboratory, such as samples, to require several barcodes or identifiers.

As long as your LIMS is configured to handle multiple identifiers for a single sample, this shouldn’t be a problem.

Applying multiple barcodes to elements in your laboratory can prove to be highly beneficial.

For example, if it’s a clinical testing laboratory, it’s possible to assign an internal barcode to each new sample received, even if it already has an external barcode associated by a requester.

With the internal barcode, you can be one hundred percent certain that each sample has a unique identification, while still maintaining the external barcode, allowing you to properly communicate the result back to the requester.

Barcodes and human-readable information

It’s common for certain parts of a barcode to contain human-readable information.

For example, a barcode that includes SAL-COV-000188 might indicate that the sample is a type of saliva (“SAL”), with a COVID-19 test order (“COV”), and is sample number 188 (“000188”) registered in your system.

There are two common forms of human-readable barcodes: the simple form, with number, sample type and test type; and the complex form, which includes sample and test type, requester, date and sample number, for example.

If your laboratory handles a wide variety of samples and tests, the human-readable portions of a barcode can be extremely useful.

Your team can immediately understand a good amount of information about a sample just by checking its barcode.

However, by embedding information into a barcode, its complexity can increase, which also increases the space required on labels — and some labels are small, with room for only a few characters.

Ultimately, it’s up to each laboratory to decide whether or not to include human-readable information in its process. Once each sample has a unique barcode, adding any other useful information to that barcode can happen if it makes sense for the laboratory.

Generating barcodes with complex logic

There is nothing inherently wrong with using complex logic to generate a barcode. Again, the only rule is that each code must be unique.

Given that, a laboratory can define its barcodes to be as complex as necessary. Using complex logic can turn a barcode into something more than a simple identifier.

By encoding multiple pieces of information into a code, the team can immediately know a great deal about the sample.

As an example, let’s use this complex barcode as a reference: SAL-COV-OP011-2020.10.10-0001. This example:

• Is a saliva-type sample (“SAL”);
• Has a requested COVID-19 test (“COV”);
• The requesting physician was asked to provide tracking number “011” from their system (“OP011”);
• Was received on October 10, 2020 (“2020.10.10”);
• Was the first sample received that day (“0001”).

This wealth of information can be read straight from this barcode, without even having to look up the sample in the LIMS.

However, this also means that the LIMS will need to process a considerable amount of logic to correctly generate a barcode for each sample.

If there’s a desire to encode more information into barcodes, you need to make sure the LIMS can generate them accurately and with all the necessary logic, while also ensuring they remain unique.

Not every LIMS has this capability. Using the previous example, some systems may not be able to easily extract information about the sample type, requested test, or requesting physician.

Some LIMS platforms may also struggle to reset the incremental sample number every day.

Printing barcodes directly from the LIMS

With the right LIMS, you can not only print barcode labels directly from the system, it’s a practice that should happen.

This ensures the accuracy and reliability of the information. Unfortunately, some LIMS solutions on the market don’t communicate with a barcode/label printer, and this needs to be taken into account when evaluating and deciding which LIMS to acquire for the laboratory.

If this function isn’t available from the start, it’s nearly impossible to add it later.

Once the decision has been made to print barcode labels, a few things need to be considered:

1. Will the label have human-readable characters and/or a readable barcode?

Most laboratories consider it essential for each label to have characters that are readable by staff. Otherwise, it becomes extremely tedious to find a specific sample among hundreds of others.

2. Should the label include a machine-readable barcode?

This isn’t always necessary, but it can prove very useful for certain workflows. If you need to quickly locate a sample in the system, a machine-readable barcode is extremely important, but not every laboratory needs this functionality.

3. Should the machine-readable barcode be 1D or 2D?

1D barcodes are limited in the information they can encode. They can only include numbers and letters, with no special characters. The longer the encoded text string, the longer the barcode will be.

2D barcodes (also known as QR codes) are the new standard for encoding information. They are highly flexible and can encode numbers, letters and many special characters.

2D barcodes also take up much less space, with long text strings easily encoded into that small square.

Regardless of which type of barcode is chosen, you need to make sure the scanner is capable of reading it. Almost all readers understand 1D barcodes, but not all of them can read a 2D barcode.

In other words, before purchasing a scanner, you need to know what you plan to scan.

Conclusion

Implementing barcodes in a laboratory is a bit more complicated than it might initially seem.

Before implementing barcodes in the laboratory, you need to be able to answer the following questions:

• Which physical elements of the laboratory need to be tracked with a barcode?
• Should the LIMS be able to generate codes automatically for the team?
• Will any laboratory elements have multiple associated barcodes?
• What type of logic is required to generate barcodes in the laboratory?
• Will it be necessary to print barcode labels directly from the LIMS?

Once all these questions have been answered, you can be confident that you’re using barcodes in your laboratory in the best possible way, increasing the efficiency and traceability of your process.

To understand how Actiz can help you manage your laboratory’s barcode requirements, reach out to us at contato@actiz.com.br. Our unique barcode functionality supports generation and printing directly from a LIMS record, visibly improving team efficiency in the laboratory.