When nonscientists think of advanced sensors, images of Star Trek’s “tricorder” often come to mind. The tricorder could detect contamination, sense approaching enemies, and give quick evaluations of an individual’s health (even one of a non-human species).
As J. Justin Gooding, editor-in-chief of ACS Sensors explains, however, this depiction of sensors couldn’t be further from reality.
On September 1, Gooding talked sensors with science enthusiasts around the world during an “Ask Me Anything (AMA)” session on the popular social networking site Reddit. AMAs are text-based discussions in which a celebrity or expert answers questions about a topic in real time. Gooding fielded questions about future directions and challenges for chemical and biological sensors.
Scaling up sensors
First, says Gooding, it’s important to understand what today’s sensors can do—and what they can’t. Unlike tricorders, chemical and biological sensors don’t detect just anything. Instead, they are designed to detect a single thing very well. (When we need a sensor to detect many things, we build arrays of sensors into a single device.) Some of the most common everyday examples of sensors are the glucose meters used by diabetics and pregnancy test kits.
Sensors are also made for situations in which there’s no time to send samples back to a lab for analysis. They must give results instantly and be foolproof to interpret.
If sensors are so useful, why don’t we see more of them than we do? “There are barriers in making many types of sensors commercially viable,” Gooding says. Markets have to be sufficiently large to justify making a particular sensor, and in many cases, applications just aren’t broad enough.
Another roadblock: sensors must be replaced frequently. In complex environments, sensors can often become “swamped” by irrelevant stimuli. This makes it difficult for them to detect what they’re supposed to. Ideally, says Gooding, we’d have “continuous” sensors impervious to distractions. But he doesn’t expect these will be available anytime soon.
Looking to the future
There are plenty of exciting innovations happening in the sensors world, however. “Single-molecule and single-cell sensors are going to explode,” Gooding says. Such sensors could be used for drug testing and personalized medicine applications. For example, a sensor could be used to identify cells resistant to cancer drugs to quickly determine whether a cancer treatment will be effective for a particular patient.
These sensors could also be tailored to detect a single diseased cell among many, or identify a molecule that corresponds to a certain sequence of DNA.
Gooding also predicts an increase in sensors for environmental and food monitoring. We could use these sensors to learn, for example, whether a water source is safe to drink or seafood safe to eat.
In addition, says Gooding, innovations in sensors technology are likely to follow developments in biology, chemistry, and other related fields. As scientists discover new and important biomarkers, sensors will be developed to detect them.