Electronic nose
The electronic nose or nano nose is an artificial olfactory device that has a small array of flexible gold nanoparticle sensors that can accurately detect compounds in a breathing sample. Currently researchers tried to use this nano nose to detect various types of cancer such as ovarian, lung and brain cancer and got 82% accuracy. Disease detection by electronic nose is safer, simpler, more portable, inexpensive and less invasive diagnostic method than traditional methods such as imaging technique, biopsies etc. The nano nose comprises of a large number of flexible sensors that are based on molecularly modified gold nanoparticles (GNPs) [1]. These sensors are integrated into a dynamic cross-reactive diagnostic sensing array. Gold nanoparticles are highly sensitive in the detection of biomarkers at lower concentration levels and they are biocompatible. Each bending state of the flexible sensor gives unique nanoparticle spatial organization, altering the interaction between GNP ligands and volatile organic compounds (VOCs) that increases the amount of data obtainable from each sensor.
The individual dynamic flexible sensor of the nano nose could selectively detect ppb (parts per billion) level VOCs that are linked with cancers in exhaled breath. VOCs can be produced endogenously or exogenously and are used as biomarkers to detect diseases such as cancer in early stages fast and accurately. For example, lung cancer tissue emits some specific VOC biomarkers such as acetaldehyde, formaldehyde, undecane, isopropene, methanol, ethylbenzene and acetone that can be detected by sensors/chemiresistors coated with gold nanoparticles of a nano nose [2]. Breast cancer patients emit VOC biomarkers that includes derivatives of alkanes such as tridecane, hexanol, formaldehyde etc and bladder, and prostate cancer patients exhaled toluene, p-xylene, acetic acid etc. This electronic nose has a huge potential to detect and diagnose various types of diseases including cancer that can enhance the opportunities to save lives.
