Nanodetectors for artificial skin are becoming more sensitive
Nanoparticles helped to make sensors for artificial skin
<url>Israeli engineers have developed flat and flexible sensors based on gold nanoparticles.
This development should help in the creation of prostheses capable of transmitting to the owner the sensations not only of touch, but also of temperature and humidity. The work of specialists from the Technion-Israel Institute is described by Science Daily (Breakthrough Could Lead to 'Artificial Skin' That Senses Touch, Humidity and Temperature) with reference to the researchers' publication in the journal Applied Materials & Interfaces (Segev-Bar et al., Tunable Touch Sensor and Combined Sensing Platform: Towards Nanoparticle-based Electronic Skin).
The declared characteristics of the sensors are as follows: they are able to register a mechanical load of several hundredths of a gram, sense temperature changes within one degree and respond to fluctuations in relative humidity up to one percent. In terms of mechanical sensitivity, the new development still loses to human skin, but it is already sufficient for many practical tasks.
The sensors are made of thin layers of gold nanoparticles bound together with a diameter of only 5 to 8 nanometers. Preliminary tests have shown that they remain functional when repeatedly bent together with a rubber substrate, and can also be placed on different materials. In addition to prostheses, the new sensors can be used to track deformations of building structures, as well as components of mechanisms: cracks will be detected with the same success as bending or twisting a part.
The principle of operation of sensors is based on the fact that an increase in humidity or temperature increases the conductivity of the tape of nanoparticles and the polymer substrate binding them, and bending leads to a decrease in the distance between the nanoparticles with a change in electrical resistance. Previously, scientists could make flat and flexible pressure sensors, but they could not register temperature and humidity.
Illustrations: Prof. Hossam Haick el al., Technion-Israel Institute of Technology – VMPortal "Eternal youth" http://vechnayamolodost.ru