A new sensor that can efficiently monitor damaging reactive oxygen species (ROS) in biological samples has been developed. Professor Tito Scaiano, University of Ottawa, Canada and colleagues have shown that their new sensor to be a useful new tool for detecting ROS in homogenous and biological systems.  

Reactive oxygen species (ROS) formed during the metabolism of oxygen are believed to cause aging and other diseases such as atherosclerosis and cancer. Researchers are therefore interested in developing sensors to accurately monitor the effects of ROS. 

This new sensor has several advantages over existing ones. Advantages include a simple and inexpensive synthesis, exceptionally contrast, and useful fluorescence in a region of the visible spectrum where cell autofluorescence is at a minimum. Scaiano talks more on his work in the answers below. 

1. Could you briefly explain the focus of your article to the non-specialist and why it is of current interest? 

Reactive oxygen species (or ROS) play an important role in many diseases, as well as in ageing; antioxidants help us reduce this damage. Sensors that allow us to detect ROS in biological systems are tools that allow us to evaluate the involvement of ROS, and possibly to map them at the cellular level. The new sensor that we call NBFhd ('hd' for hydrogen donor) is easy to prepare, has excellent contrast (i.e., the difference in signal between ROS-free and ROS-exposed samples is very large) and its fluorescence does not overlap with cellular autofluorescence. Its fluorescence develops when ROS are formed in systems that lack some key antioxidants, such as Vitamin E. 

2. What is your particular interest in this area of research? 

We have a general interest in oxidation and antioxidants, and in this case in developing the tools to study these processes. 

3. Where do you see this field developing in the future? 

From a research perspective, we believe that computational chemistry will lead the design of future fluorescent probes for ROS, or other reactive species. Ideally given a set of experimental requirements one should be able to come up with a few promising structures. Then, one would use ease of synthesis as a criterion for identify the best candidates. 

From the point of view of applications we believe that this probe will prove useful for high-resolution optical microscopy, allowing the mapping of intracellular processes and perhaps reach even the single molecule level. 

4. Are there any particular challenges facing future research in this area? 

Developing probes that have improved fluorescence quantum yields would be highly desirable for the microscopy applications mentioned above. Structural modifications would be expected to direct the reaction predominantly towards pathways that enhance fluorophore release.