Spanish engineers developed new humidity sensors to fight bacteria production in highly humid environments. Across various industries, humidity is one of the most monitored and controlled operations aspects.
But there are still many problems that threaten the monitoring and controlling processes, especially in environments with very high levels of humidity. Bacteria multiply in environments where with the humidity levels are very high. This results in the "biofilm" formations, which are ecosystems of microorganisms that are typically attached to a surface.
Biofilm formations on surfaces lead to material deteriorations, which often affect the devices, including its performance and service lifetime. The deterioration process due to biofilm formation is known as biological fouling or "biofouling," which refers to the buildup of microorganism on wet surfaces.
"Right now, the costs arising out of biofouling are very high mainly because of the maintenance work or replacement of equipment," said engineer Aitor Urrutia from Spain's Universidad Pablica de Navarra (UPNA).
Urrutia and team developed novel humidity sensors with antibacterial properties for devices that work in high humidity environments. These new humidity sensors prevent biofilm creation and help solve biofouling.
Using a combination of nanotechnology and latest developments in fiber optic, the new humidity sensors have improved performance and longer service lifetimes. The humidity sensor has an optical structure that is coated with silver nanoparticles. The coating is less than one micron thick.
The humidity sensors are biocompatible and immune to electromagnetic interference. They are also inexpensive, compact and lightweight.
The new humidity sensors can be utilized in various industries, including food processing, biotechnology, pharmaceutical industry, home automation, health clinics and hospital. It could help in monitoring human respiration among others. Since the sensors are compact and lightweight, they can be used to monitor humidity levels in areas that have limited access.
"Thanks to the embedded silver nanoparticles included, these coatings provide the sensors with two additional functionalities: antibacterial properties and increased sensitivity," said Urrutia.
Department of Electrical and Electronic Engineering lecturers Javier Goicoechea-Fernández and Francisco J. Arregui-San Martín supervised Urrutia's PhD thesis. The study was published in the journal Nanoscale Research Letters on Dec. 29, 2015.
