Label-free analysis has made its way in the life sciences and has become a valued tool e.g. in pharmaceutical research. This is mainly due to its outstanding depth of information in combination with its reliable data quality. Yet, many other areas of application might benefit from certain advantages of label-free methods that remained largely unexploited so far.

Benefits of label-free technologies

One major plus factor of label-free technologies is the ease of sample preparation and measurement. Once a testing protocol has been developed and established, the actual measurement can’t be any simpler: without the need of any pre-incubation, any mixing, stirring, diluting etc. many samples can directly be injected into the instrument which in turn handles all upcoming steps of liquid handling and readout. This characteristic has two major advantages: first, no specifically educated personal is required but the measurement can be carried out by any employee after a short training. Second, the easy sample handling and the minimization of hands-on steps make label-free techniques very fast. These two benefits taken together recommend label-free analysis for all situations where time is an issue and no educated personal is available.

“Label-free analysis is recommended for situations where time is an issue”

Civil security

Let me draw one picture to elucidate this thought: Imagine a quite common situation at an international airport: One passenger suddenly collapses during the flight and it is required to exclude any potential infectious disease before the co-passengers and the crew leave the airport. In this situation, both criteria outlined above have to be fulfilled: first, it cannot be assumed that any medical doctor is available so that testing has to be operated by e.g. security officer. Second, time is crucial in that situation as passengers shall not be slowed up by the testing procedure and the results must be available before they pass the customs. In addition to these requirements that can be met by almost any label-free technology out there, the outlined situation is especially challenging as the test must be good for a large number of potential infectious diseases. Therefore, a parallelized measurement setup must be provided that allows multiplexing of hundreds or even thousands of tests. This way, basically any disease can be tested in parallel as soon as there are e.g. specific antibodies available. With low costs per analysis, such an assay would be ready for next generation homeland security and protection against epidemics.

“There is an intense need for a label-free platform which is affordable and easy to operate.”

Disease control

Another security application that can benefit from inherent label-free advantages might be the screening of numerous people against one specific pathogen. While this can be achieved with standard immunoassays at low cost, these formats suffer from the lengthy and complicated sample preparation procedure. Here, the benefits of streamlined operation and short cycle times of label-free technologies again come into play. However, conventional label-free technologies are expensive in terms of both, instruments and sensor chips, and are thus not suited for this application. Hence there is the intense need for a technology which offers both, an affordable and easy to operate instrument platform and low cost consumables. This way, e.g. all immigrants from a region with an acute epidemic could be tested at the entrance site.

What comes next?

These two examples are pointing towards new areas of application for label-free technologies and many more can be imagined. The basic idea behind these fields of application is to understand label-free methods as easy to operate systems with outstanding data reliability rather than a sophisticated tool for state-of-the art research projects.

To rethink the application areas of an entire technology it requires a community of scientists, users, manufacturers and official representatives ready for thinking ahead and breaking barriers.


The author

Dr. Frank Schleifenbaum is holding a PhD in physical chemistry and is heading an independent research-group in biophysical chemistry at the University of Tübingen.

To find out more about his work visit his website.

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