Applications of Animal Biosensors: A Review

Odorous compounds perceived by humans or animal species produce a response in chemical- or electronic-based analytical detection systems (chemical sensors, electronic noses, gas chromatography, mass spectrometers, and so on). Animal noses can also produce a recognizable behavioral response in the animal, when exposed to those compounds. Recently, much attention has been paid to the use of animals for scent detection based on their behavioral responses, referred to as animal biosensors. So far, behavioral odor detection by animals has been applicable in some fields, such as forensic sciences, homeland security, or, more recently, cancer diagnostics. The major advantage of animal biosensors is that the animals can be conditioned rapidly and cost-effectively, offering benefits in terms of noninvasive detection and early diagnosis. Here, we review the applications of living biosensors as whole animal biosensors and discuss the main issues, approaches, and challenges.