In virtually every field – be it science, sports or even military tactics, a specific strategy can only be designed with a clearly-identified target in mind. If this is not available, one would instead develop a wide array of countermeasures and scrutinize them to verify their effectiveness.

This is the methodology adopted by the Chemical Cellomics Lab led by professor Young-Tae Chang at the Department of Chemistry, POSTECH: the Lab is building a ‘library’ of more than 10,000 fluorescent molecules to literally illuminate any target molecule. The ultimate aim of such endeavors is to capitalize on fluorophores as ‘identifiers’ that are immediately visible and demonstrate the highest reaction sensitivity in order to create sensors capable of detecting any substance in question.

For the most part, research intended to engineer identifiers focuses on identifying a specified target. Detecting the caffeine level of coffee serves as a case in point: most of this kind of research begins with the discovery of the identifier that accurately detects only the caffeine before moving on to further refine the identifier. The problem with this approach lies in the fact that it won’t produce the expected benefits as coffee contains numerous substances that interfere with the efficacy of the identifier.

This has prompted professor Chang’s research team to embrace just the opposite approach: team members firstly arrange a massive set of identifier tools and then look for the identifier that reacts most effectively. This approach can be likened to how the human immune system prepares hundreds of universal antibodies and creates diverse combinations from these antibodies to respond to millions of external substances that enter the body. Whereas concentrating research on any specific identifier may reduce the versatile application of its outcomes, this library-based approach enables researchers to respond to any possible target. Thus far, the research team has built a library of more than 10,000 fluorescent identifiers, a record to which no other laboratory in the world can even dare to match.

The Chemical Cellomics Lab strives to fulfill two overarching goals: firstly, it wishes to serve as a detective agency that creates an effective system that immediately identifies any target substance its client seeks to ascertain. Practically, this can be as simple as dropping a bead of identifier (harmless to the human body), into a cup of water to instantly judge if the water is safe to drink. The application scope of such a system is virtually limitless. One of the Lab’s most recent assignments was to identify the freshness of the oil contained in Chinese hot pot dishes whose deep red color makes it challenging to tell whether the oil has been changed or not.

The Lab’s second goal is to distinguish more than 200 types of human cells. Let’s take cancer cells for an example: while healthy immunocytes successfully destroy cancer cells, unhealthy immunocytes actually contribute to their growth. This leads researchers to believe that just the classification of these cells alone will aid in the treatment of cancer. In improving the depth of its understanding of these microscopic worlds both systematically and thoroughly, the Lab will inch ever closer to its ultimate aim in creating the Human Cell Atlas.